This review contains plot spoilers.

A few weeks ago, 'Kill the Moon' sparked debates about whether Doctor Who needed to get its science right: was it science fiction or fantasy? This week there seems little room for debate: this is surely outright fantasy, from its fairytale roots through to its magical branches and leaves. Rather than gothic monsters there are glowing motes of sentience; in the place of technobabble there are “voices” that children can hear. Writer Frank Cottrell-Boyce is, of course, not only a Carnegie Medal winner for children’s fiction, he was also the writer of the 2012 Olympics Opening Ceremony, where a gigantic tree was uprooted in order to symbolize the industrial revolution’s onset. In short, Cottrell-Boyce is no stranger to the dense symbolism of trees, woods and forests, and here again he tackles nature versus technology, with the Doctor and his sonic screwdriver appearing powerless to turn back an invasion of the trees.

Almost lifting his title from a William Blake poem, Cottrell-Boyce is clearly committed to Doctor Who as an educational show. Indeed, writing in The Telegraph on Saturday August 23rd he also compared the many Doctors of the show’s history to Philip Larkin’s poem ‘The Trees’:

Perhaps part of the show’s deep appeal is that it offers this possibility of renewal, of starting again. The Doctors are like the trees in Philip Larkin’s poem, which “die too” but whose “yearly trick of looking new / Is written down in rings of grain”. “Last year is dead, they seem to say / Begin afresh, afresh, afresh."

And there’s certainly a freshness to this rather unusual Who. The episode fizzes with ideas, especially when Cottrell-Boyce comes up with his own explanation of “bigger on the inside”. It’s a moment that’s sold wonderfully by Sheree Folkson’s direction. Rarely has the TARDIS console room felt as awe-inspiring as when Folkson has the camera track Peter Capaldi’s walk up the stairs and around the outer wall, effectively seeing it all through the dazzled eyes of young Maebh (Abigail Eames).

There’s also more than a touch of Malcolm Hulke’s old-school storytelling to this adventure, with the Doctor and humankind confronting a power that’s always been there – though these ‘tree devils’ aren’t quite what they seem. Meanwhile, the beautifully unsettling image of a green earth hits home with an ecological message that’s far from subtle. This authorial vision of Doctor Who is probably the closest thing to James Lovelock’s Gaia theory that TV drama has ever sustained, even edging out the classic BBC thriller, Edge of Darkness.

In some ways, though, this is anti-Doctor Who: the Doctor and Clara are ultimately on-lookers, and Missy is similarly reduced to doing little more than watching the outcome of events, albeit with surprise. The Doctor’s role in the story is definitely trimmed back: although he works out what’s going on, and helps Maebh get word out to the authorities, he still ultimately watches the trees in action with a degree of uncertainty. In contrast, Danny Pink gets much more to do than usual, showing his mettle as a leader; Cottrell-Boyce perhaps wants to demonstrate ‘ordinary’ human powers at work, whilst minimizing or cutting back on the conventional fantasy-hero’s role. And what John Tulloch and Manuel Alvarado, writing in The Unfolding Text, call one “of the recurrent motifs of Doctor Who” (p.94) is also inverted. In place of “organic” nature threatened by bad or mad scientists, science is alternatively trumped by nature’s fantastical potency. These trees run rings around both Time Lord and humankind.

But Doctor Who reimagined with a type of fairytale ambience – far more so than ever before in the Moffat era, despite previous attempts to position the show in these terms – also has certain limits. The script is sometimes in danger of becoming a touch twee, and its ending is arguably slightly weak. The brief final scene feels forced and tacked-on – there simply because another moment of emotional closure is needed. For a screenplay that has otherwise refused to play by a number of Doctor Who’s ‘rules’, this final capitulation to yet another happy ending doesn’t quite ring true.

'In the Forest of the Night' wants to revalue fairytales at the same time as reinforcing its ecological thesis. At one point, it’s suggested that forests represent a primal symbol of fear (“the forest is mankind’s nightmare”, says the Doctor), and it would have been interesting if the episode had taken more time to tease out and develop this possibility. But psycho-drama is rapidly displaced by eco-lecture. And so instead forgetting is identified as “the human superpower” (did Moffat’s ‘Listen’ riff on Cottrell-Boyce’s ‘Forest’, or was this an arboreal coincidence?). Fairy stories are shown to be less strange than the episode’s 'real' events. In this reversal, fairytales are an echo of magical reality and not just a mode of childhood fiction. Despite appearances, 'In the Forest of the Night' doesn’t merely reference fairytale archetypes; it’s an argument for the uses of enchantment and the values of the fairytale, not just in terms of making readers and audiences feel safely thrilled, but in reminding us – children and adults – of the strangeness and wonders that can exist all around us, before us and after us.

Having a Carnegie-winning writer of children’s fiction contribute to series eight was undoubtedly a press release-worthy event. But following two impressive episodes from Jamie Mathieson, especially the visually stunning and tightly coherent 'Flatline', 'In the Forest of the Night' doesn’t stand out quite as much as may have been anticipated. It is very much ‘Frank Cottrell-Boyce does Doctor Who’, and as such has a far stronger authorial voice than the show sometimes permits guest writers. Yet by reducing Clara, the Doctor and Missy to spectators gazing with wonder at a global spectacle, this story felt more reminiscent of the London 2012 Opening Ceremony than I would ever have imagined.

This review contains plot spoilers.

Nine weeks in, and it's time for a 'Doctor-lite' episode, as Clara Oswald's journey continues. Last week, in Mummy on the Orient Express, we saw her consider her role as the Doctor's companion post-wobble. This week, she's had a shock promotion - it's her turn to be the Doctor.

Arriving on present-day Earth, we're immediately in uncharted territory for Doctor Who - Bristol. They should have taken the time to look up Chris Parsons, and see if he moved back to the area after all that business with Skagra and that sphere in Cambridge. Hopefully he'd live in the nicer part of Bristol, which we don't see here. The TARDIS arrives on a wasteground, and the first place Clara visits after that is a dingy underpass. Other locations include a warehouse and a railway tunnel. It's not doing Bristol's tourism industry any favours.

After a brief, creepy teaser, the story quickly gets down to business - the TARDIS is rapidly shrinking with the Doctor trapped inside, and lunch with Danny Pink is off. Clara is left to investigate, with the trapped Doctor as backseat driver - giving her the sonic, an earpiece and hacking her optic nerve.

Clara soon happens upon a Community Service team led by nasty-piece-of-work Fenton (Christopher Fairbank), and teams up with one of the group - Rigsy (Joivan Wade), a likeable young man with a penchant for street art. From the start Rigsy is portrayed as a good sort, while Fenton is an unrepentant bigot and bully throughout, and nearly gets everyone killed. Even the Doctor's moved to say that not all the right people were saved at the end.

Fenton's crew are tasked with painting over murals that have appeared alongside tributes to recently disappeared locals. The murals are of people with their backs turned. It soon transpires that they're not murals. A sinister alien force is at work - one that exists only in two dimensions. It's dissecting and analysing us, a slow-dawning realisation that hits when the Doctor twigs that the strange decor on the walls of the flat of one of the missing people is actually a flattened out human nervous system.

The alien threat is unnamed, doesn't speak, and has unknowable, yet nasty motives. We never learn anything about it - even whether it's a single entity or a race - but its theft of our dimensions, and our image is a disturbing concept. The concept of people turning into drawings was of course done way back in Fear Her, but there's no upbeat reversal of the situation here. The Doctor is briefly given pause to ponder whether the aliens' (or alien's - we don't know for sure) M.O. isn't necessarily bad, but his mind is made up by the end, and his fury is something to behold. The stop-motion-styled flowing effect as people are absorbed into the walls and floors is creepy, as is the jerky, misshapen movement of the painted figures chasing down the railway tunnel. Once upon a time Doctor Who made kids afraid of shop window dummies, telephone flexes, and statues. It recently branched out to bedsheets. Now it's moved on to walls, and floors.

Douglas MacKinnon does an excellent job of directing as ever, all long shadows and atmosphere, with some excellent camera trickery and physical comedy - as the Doctor's hands and face portrude impossibly from the shrunken TARDIS. Clara even pulls a sledgehammer from her handbag. Jamie Mathieson delivers his second cracking episode in a row - more from him please.

Danny Pink appears again, in another cameo - the third in a row since his last full appearance in The Caretaker. It's hard to see where his character is going from this, and Samuel Anderson's a bit wasted here - hopefully his story will finally pay off in the next few weeks.

For a Doctor-lite episode, the Doctor is much more present than usual, albeit trapped in an ever-diminishing TARDIS. Capaldi and Coleman continue to impress. Both get some great lines, and the Doctor and Clara's relationship is now in a very interesting place. She's thoroughly pleased with herself about how well she handled standing in for the Doctor. She wants his approval. He eventually compliments her, but seems a little troubled at how well she did at 'being' him, and also at how easily she lies to Danny about still travelling with him. Perhaps his influence isn't healthy, and he seems to acknowledge this.

We end by cutting to Missy, watching Clara (somehow - how does she do that?) on her white iPad, remarking how glad she was to have chosen her. We'll find out what for in a fortnight, but it's unlikely to end well.

This review contains plot spoilers.

"You know Doctor, I can't tell if you are a genius or incredibly arrogant',.. "On a good day I'm both". - Perkins to the Doctor

What a romp and what a showcase for Capaldi. This was always the breed of story I hoped to get when Steven Moffat was first confirmed as showrunner. It has the heart of Doctor Who's golden period from 1974 to 1977 when Tom Baker was at his peak but also slots in very comfortably with a 2014 autumn schedule on a Saturday night. Doctor Who has often borrowed its own past successes and done something new, often to great effect. Thanks to a very capable director in Paul Wilmshurst (who continues to impress after 'Kill the Moon') and a more than competent script this is definitely one of those winners.

The story is remarkably simple without being too predictable. Various passengers from all walks of life on the Orient Express are being targeted by a remorseless creature that only they can see and feel. Despite their understandable panic there is only confusion from the people around them and nothing can be done within the span of Sixty-Six Seconds. And the Doctor realises that he is facing a stern test of his ability to come up with a solution. This is not a murder mystery for a Poirot or Marple and not everyone is playing by the rules..

The haunting killer of classic Who's 'Mind of Evil' is subtly referenced in the threat the Mummy presents - only the victims can see it . The way that it can move anywhere and not be stopped by physical items like bullets or locked doors is a perfect way to scare the junior members of the audience. The gimmick of having there be a visible counter remorselessly marking the moment of demise on-screen is somewhat odd but does come off - at least until Gallifrey's favourite son pulls off a beautiful trick (which doubles as an homage to Moffat's very first televised story).

The Orient Express is one of many in the cosmos and history, but this particular one rattles through the vacuum of space relentlessly, caring little for its appearance compared to other vessels that normally occupy this zone. It also used to be a tour through an area of the galaxy that had many a remarkable planet. However although this appears to be just another one of many journeys, there is a real twist when the whole vehicle is shown up as nothing more than a laboratory for testing a sample group. Although it is perhaps not totally watertight as the TARDIS has clearly broken into the environment!

What is clever is that quite a few of the victims are not all that likeable, or perhaps we catch them on a bad day. This is very welcome as it means that what normally is just monster fodder is something else and links in smoothly with the whole amoral presentation of this new Doctor which has fascinated many viewers since the season premiere. Also commendable is how the Doctor gets caught out several times - once when he casually mentions knowing a particularly memorable planet, now long-gone. This is put to effect later with an impact on the overall drama when the psychic paper turns out as not a simple plot short cut after all. The Doctor is realistically challenged, but such is his ego he will have none of it, and as bodies pile up his hubris and ruthlessness only seem to magnify.

When it comes to actually saving the day, it turns out to be a pyrrhic victory. A good number of people get back home unscratched. Some of the apparently threatened passengers were only hard light holograms and so were never really at risk. But lives are lost and not just to the sinister bandaged antagonist. Other carriages with real living people are broken into and the bodies are left to float in space, most likely forever. And this is a direct consequence of the Doctor's efforts: he does get the right end result, but only after a fatal trial-and-error procedure. The Twelfth Doctor may not react too overtly to this disturbing turn of events but he surely knows he could have done something different.

Guest stars are all up to the standards the better episodes have set previously, with a welcome cameo from talented singer Foxes and a nicely balanced guest role for Frank Skinner as Perkins. When he first appears there is ever so slightly an element of creepiness as appears rather indifferent to an old woman's death; but then perhaps he didn't take kindly to being looked down upon as was implied by what little we saw of her. I won't claim Skinner is as good an actor as he is a comedian but he still fits the particular role quite handily. Having Capaldi around certainly helps too as he effectively assumes the role of guest companion. His eventual moment in the TARDIS is also wonderful. The sheer exuberance that someone experiences from seeing dimensional transcendence is a trope I will never tire of. Meanwhile Clara is forced into another section of the train and interacts quite significantly with Maisie - herself a fine one-off character that very much needs saving by the Doctor.

Yes, she did not storm off after all, despite all the signs being there. Clara perhaps more predictably is the voice of morality again; with her friend admitting he could not do anything until he had all the facts at hand. That they are still together is a result of their deeply held admiration and respect. Purely liking one another as most platonic friends doesn't come into it, but then how many friends are there who are come from different planets and have such contrasting life spans?

Danny once again takes a backseat role the second week running, but the arc is still being explored in interesting ways. His seeming acceptance of Clara's hectic lifestyle and how the Doctor really cares on some level despite all his harmlessness is interesting if perhaps a little forced. I do welcome character development for this year's new star of Doctor Who and I am being won over gradually. However in all honesty I still find Samuel Anderson somewhat underwhelming in relative terms, especially if I were to compare him to Arthur Darvill who was rather similar in function.

Although the resolution sees the doctor disable the Foretold and use part of its core to save everyone remaining on the train, there is still no sign of the real threat who caused the crisis in the first place. This is a good idea and knowing Moffat there is as much chance that the answers come next season as they do by the closing twelfth episode of this present run of episodes. So we are left with a rock solid story that can stand up on its own and reward many a viewer's time, but also is well-woven into Series 8. I eagerly await the next Jamie Mathieson effort; conveniently enough it is scheduled for next Saturday evening.

This review contains plot spoilers.

Every now and again, an episode of Doctor Who comes along that divides and conquers at the same time. Kill the Moon could be that episode. It subverts expectations, and not just those of the viewer - nobody in this story gets what they expected either.

The episode begins with a quick scene-setting moment of Clara and 'disruptive influence' Courtney Woods on the Moon in the year 2049, broadcasting a message - they have a terrible decision to make. We then flash back to the present day at Coal Hill School, where Clara is giving the Doctor a piece of her mind for taking Courtney for a spin in the TARDIS at the end of The Caretaker, then telling her (off-screen) that she's "nothing special". Suddenly faced with an unhappy companion and a clearly distressed teenager, the Doctor makes the snap decision to take Courtney to the moon to try and make up for it, with Clara still on board. They arrive, not on the Moon, but on a dilapidated space shuttle heading very rapidly for it. A space shuttle full of nuclear bombs.

They are confronted by Captain Lundvik (Hermione Norris), and her two crewmates Duke (Tony Osoba) and Henry (Phil Nice). Lundvik's crew are on a desperate mission. The Moon has put on weight, and the Earth is being crushed under the pressure. Humanity is at the brink of extinction. Space travel at this point is in the doldrums, the last mission to investigate was ten years previously, and the Mexican crew disappeared without trace. Lundvik's crew have liberated a shuttle from a museum and are there to destroy the Moon. Norris is good as Lundvik, who comes across as cold and calculating, but in reality is a desperate, numbed woman on a suicide mission. Her cohorts, sadly don't get much to say or do. If this was Star Trek, they'd be wearing red shirts.

The Doctor is instantly on the case, noting that there is gravity where there should be none, and that the Moon is breaking up already. They investigate the base set up by the Mexicans, only to find it deserted except for cobwebbed and space-suited corpses. New Director Paul Wilmshurst wastes no time with the scares - there's something hiding in the shadows of the moodily-lit base, and in craters, some rather nasty spider-like creatures that make short work of Lundvik's crewmates. There's a brilliantly tense scene where the Doctor and co. attempt to escape a 'spider', and Courtney is trapped on the ceiling of a room with one when the gravity fails. The Doctor of course gets her back on the ground, and Courtney herself deals with the creature, but this is when the story starts to change from a straight scare-fest into a very different beast, from Philip Hinchcliffe scares to Malcolm Hulke moral grey areas.

It's all getting a little too real for the clearly scared Courtney, who asks to go home. The Doctor doesn't put up much of a fight, but locks her in the safety of the TARDIS while he continues his investigation. Ellis George is very good as Courtney. A whole episode of a teenager snarking in this scenario would be annoying and unrealistic - she shows that she's scared and cares enough about the situation to want to help, but even in the face of armageddon the shields are up, and she prefers to call Clara 'Miss'.

Paul Wilmshurst's direction is exemplary. He makes stunning use of the Lanzarote location as the lunar surface, and will doubtless traumatise a fair few youngsters with those vicious, screaming spiders. More from him please. New writer Peter Harness is also a real find, deftly handling scary and weighty with enough room for a joke about tumblr which other writers may have made into purest driven cheese.

The spiders are actually a form of bacteria, and the Doctor soon realises that the Moon isn't just a pile of rock orbiting the Earth. It's an egg, an egg with a very long gestation period - and it's hatching. A unique baby is about to be born.

Lundvik still wants to know how to kill it. Humanity is still at risk. Clara and Courtney insist that it's wrong to kill a baby. Clara turns to the Doctor to make a decision. And he walks away, disgusted with Lundvik who has primed the bombs, but adamant that this isn't his decision to make, snapping that it's time to take the stabilisers off the bike, and leaving the three women forty-five minutes to make a decision. Doctor Who is tackling abortion, and the Doctor has abdicated his responsibilities.

Clara puts it to the public vote. Humanity predictably chooses itself, but at the last moment she hits the abort button, and the Doctor reappears and whisks them back to Earth, where they witness the creature's birth from afar. You don't quite get a good look at it, which leaves something to the imagination. It lays a new egg to replace the old one before it flies away in peace.

Wrap up time.The Doctor makes a stirring speech about today being a turning point for humanity. Lundvik thanks Clara for stopping her from destroying an innocent life. Courtney heads for double Geography in the knowledge that she was the first woman on the Moon. All's well that ends well. Except when it doesn't.

Clara has been fairly subdued throughout, but is furious with the Doctor for leaving her with such a huge decision that she could so easily have got wrong. He gently tries to convince her that he knew she would always make the right decision, but it doesn't wash with her. He's patronised her and scared her out of her wits, and she makes a good point - he walks our world and breathes our air, so when we need him he bloody well needs to be there for us. The exchange ends with Clara telling the Doctor to go away and stay away.

Capaldi and Coleman are both excellent. The Doctor is still blunt, rude, and difficult, but he shows a slightly softer side towards Courtney and shows no hesitation in rescuing her, and a certain manic glee as he rushes around investigating. Likewise, he's warmer than usual towards Clara and clearly trusts her to make the right choice based on her character and his bluffing about history, despite how it backfires for him. The fangs are out however, when he makes his comment about the bike stabilisers. This Doctor feels he was in the right to step back and let history decide itself, and feels vindicated when the creature swoops off and the crisis is over. It's a bold choice to let the Doctor do this, clearly the 'Am I a good man?' arc is heading somewhere. How much of this he'll take on board is anyone's guess, but I'd imagine his mind will be well and truly made up by episode twelve.

Coleman, meanwhile, is notably less bubbly than usual for the bulk of the story, but is startling at the end. We've seen a tearful Tegan Jovanka say that it's not fun anymore, and a brave-but-upset Martha Jones leave the TARDIS to be there for her traumatised family - but Clara's scathing fury at the Doctor is something new. Leaving was never like this before. And it really feels like goodbye.

A brief coda follows, with Clara pouring her heart out to Danny, who tells her that if she was really done with the Doctor, she wouldn't be so angry. This feels tacked-on, doubtless to give a note of hope that Clara will reconcile with the Doctor, (of course she will) and to give a little hint to the continuing mystery of Mr Pink's army days - but personally I feel this takes away from the brilliant scene that precedes it.

Anyway, this quibble aside, this is an excellent, thought-provoking, and very grown-up piece of Doctor Who. It's not a comfy ride - and it's sure to prove divisive from its themes and the Doctor's vanishing act, but it's fair to say the stabilisers are off for this one.

Before we get to Peter Capaldi’s seventh episode as the Doctor, Kill the Moon, halfway through the season would seem a good time to see what we’ve learnt about the Doctor. Not surprisingly, nothing is cut-and-dried. If anything, every episode thus far has shown a different side to the Doctor, and a different mood, not all of them pleasant. In fact, they’re mostly bad moods, but that’s not necessarily a negative thing. Let’s have a look at the first six episodes, and the moods the Doctor displays.

Deep Breath: Angry Doctor
In his first story, the Doctor is angry for a number of reasons: he’s just regenerated, he’s confused, and he’s not happy with an older face – especially those eyebrows (but he quite likes the new accent). He’s experienced some memory loss, he’s not sure how to relate to people, most importantly Clara, but by the end of the episode, he’s calmed down enough to know he needs Clara’s friendship – and he asks her for it too, with a little help from his previous self’s phone call.

Into the Dalek: Cold Doctor
While the Doctor finds the thought of a good Dalek confronting and challenging, his focus on the mission to go inside Rusty and ‘fix’ it is very tight, and he can’t spend time showing compassion or grief when Ross is killed by the Dalek antibodies. He’s removed, emotionally distant, and even he isn’t sure if he’s a good man. It’s all a mask, of course, to protect him, in the same way his previous selves used bravado and gleeful excitement as masks, but not as endearing.

Robot of Sherwood: Grumpy Doctor
This less-than-endearing Doctor continues here. He’s disappointed that Clara wants to meet a legend rather than a real historical figure, and he’s irritated by Robin Hood, his merry men and their laughter and banter – maybe it reminds him of his previous selves’ modus operandi. And he’s annoyed that he’s proved wrong about Robin Hood. But then at the end, he drops the pretence, and we see the unwilling hero behind the mask.

Listen: Scared Doctor
The mask drops further here. There is something under the bed, it scares the Doctor because he doesn’t know what it is, and he doesn’t like that. So he sets out to find out what it is. Rather than putting himself on the line, he uses Clara to explore this universal dream. Thanks to her distraction though, it’s Danny Pink who’s the unwitting subject, until Clara is taken to the Doctor’s own childhood and his own fears.

Time Heist: Driven Doctor
In the same way the Doctor did in the Dalek mission, he takes control of the bank heist and assumes command, seemingly unconcerned by the other team members’ feelings. He’s not sure who the Architect is, and why they’re breaking into the bank, but he knows they’ll only find out by completing the impossible mission at any cost. Luckily the actual cost isn’t that dire – something that he himself set up, and once again, showing that under his brittle exterior two very compassionate hearts still beat.

The Caretaker: Jealous Doctor
While he goes undercover at Coal Hill Secondary School, ostensibly to see k out the deadly Skovox Blitzer, the Doctor is secretly investigating Clara’s private life, specifically her ‘boyfriend’. And he gets that wrong too. He knows, despite the feelings he still has (and can’t quite express) for Clara, regardless of his regeneration, he’s not her boyfriend, and won’t ever be. But he still wants her to be happy. That’s why he looks at Adrian and sees something of his previous self, and assumes that this is Clara’s love interest. He’s not happy when he discovers Danny is her actual boyfriend, and he’s jealous. Because he doesn’t like military men and takes an immediate dislike to Danny, and because he believes Danny’s not good enough for Clara – something that Danny challenges him on.

The Impossible Girl
But enough about the Doctor. Let’s talk about Clara. What does she think of the Doctor? Because she really is the voice of the audience, whether they are hardcore fans or just casual viewers. In Deep Breath, not only do we see her struggling to accept this new/old face of her friend, but it’s addressed overtly, specifically in the conversation she has with Madame Vastra about veils and perceptions. In subsequent episodes it’s obvious that she still enjoys travelling with the Doctor – with reservations – but she’s not yet ready to let Danny in on the secret, at least until she is forced to in The Caretaker. She is, like the audience, slowly getting used to this new Doctor and his moods. She may not like everything he says or does, but she remains faithful to him and is willing to give him a go. And that too is made obvious in Time Heist, when Psi notes how often she excuses his bad behaviour. And with Danny in the picture now, we’re seeing a more complex Clara. She’s not just the perky cheeky Impossible Girl – she too has her secrets and faults.

In the Pink
As for Danny Pink, he’s a character that’s developing quite nicely. Cast from the same mould as Mickey and even Rory, but with more baggage and backstory, it didn’t take him long to work out the Doctor, and seeing that develop will be quite the treat. So bring on the next six episodes and let’s see what else we learn about the Doctor, Clara, Danny – oh, and Missy too…

Clara Oswald had been doing a good job of leading a triple life lately, but something had to give.
She was already a teacher of unruly teenagers at Coal Hill, and assistant/carer/conscience to a newly unpredictable Time Lord to start with. As if those two factors weren't enough to contend with, now she's in a new relationship too, with Danny Pink. She's struggling to keep them separate, as she careers breathlessly between adventures and dates. She's eating two dinners in a row, going for a run after running down corridors, fishing seaweed from her hair. She's flagging. The control freak in her is working overtime trying to keep her worlds from overlapping. She seems slightly uncomfortable that the kids all know about her and Danny. She really doesn't want the Doctor and Danny even knowing about each other. So, when a very familiar looking relief Caretaker shows up in the Coal Hill staff room, she's appalled, and Danny instantly suspects that Clara already knows this man...

The Doctor is being proactive again, and has decided to go 'deep cover' to sniff out the threat. His version of deep cover is to basically put on an overcoat. His latest incarnation can't be bothered to try and fit in with the natives, particularly the P.E. Teachers. He makes angry signs, disrupts lessons, and even breezily shows pupil-with-attitude Courtney the TARDIS interior. Imagine if this incarnation had been the one exiled to Earth, he would have gone stir crazy. The Brigadier would probably have had him locked up next to the Master.

The threat is the deadly robotic Skovox Blitzer, drawn to the area by decades-worth of artron energy. It's a curious thing, another lone-gunman, a diminutive metallic soldier awaiting orders - scurrying around like a toy Racnoss. It's certainly very good at blowing things up - and people, like that poor Policeman, who meets a grisly end.

It's not a great villain, and although the design is novel, it's hard to believe that this critter could really take out the entire world. This series is getting quite robot-heavy. That said, this story isn't about the Skovox Blitzer. It's about the Doctor and Danny's relationships with Clara, and how they meet and reluctantly reach a grudging respect for each other, despite this Doctor's pronounced dislike of soldiers, a theme that has been prominent in this series, and looks to continue. 

The Doctor and Danny predictably clash, it's an interesting clash too, as normally when presented with a boyfriend figure it's not so much of a fair fight. Danny, being more of an alpha male, gives as good as he gets. Clara, meanwhile, doesn't end up having to choose between the men in her life, but does blurt out that she loves Danny. This, and Danny's inevitable role in the resolution help his case with the Doctor, who wants to know she's with someone good enough for her. Danny, meanwhile, wants to know Clara is safe. Although all three are at peace at the end of the episode, there's clearly something building, and we're probably due some turbulence and heartbreak soon.

Capaldi, Coleman, and Anderson are all excellent in this. Capaldi gets some zingers from Gareth Roberts and Steven Moffat's very funny script, and also the chance to run the gamut from boredom, rage, and a knowing little moment of vanity when he mistakes another teacher for Clara's boyfriend. His Doctor also gets to bond with the equally bolshy Courtney, who's back next week for a trip to the Moon, where bad things are likely to happen. Jenna Coleman gets better and better every episode, Clara continues to come into her own, and her chemistry with Capaldi is a joy to watch. She's equally good in a quieter way with Anderson, who continues to knock it out of the park with a subtle, well-judged performance.

The only criticism? More threat next time please. Although, looking at the teaser for next week, there's unlikely to be a shortage of that. See you on the Moon.