The plot is that the Doctor and Romana land on a cargo ship carrying human sacrifices to the minotaur-like Nimon. The Nimon promise whatever the leaders of a world want but con them to consume those worlds. The leader (Soldeed) is played as an over the top leader who only desires military conquest. The victims are not well acted not are their characters well developed. Originally aired during the holiday season 1979-1980 there are a number of laughs and it plays like a pantomime. I hadn't seen this story since the late 80s and I remember that when I had seen it for the first time it was not one of my favorite stories.
However I watched this recently with my 8 year old daughter. She was riveted for all four episodes and especially enjoyed K9.
The Nimon costume was a huge bull-like head with yellow horns. The face is not animated in any way so it is not clear if we see the face or if this is a helmet. The body was covered with black nylon and 6-inch platform shoes to suggest a hoof-like foot. These monsters seemed intelligent but they had slow-moving stiff bodies and roared so much (for no apparent reason) that they always warned our heroes before they are about to turn a corner in the labyrinth. I think that they looked hilarious, but my daughter accepted them as proper monsters although she said that they were weird. As a species the Nimon just dont work for me. There is no biological explanation other than comparing them to locusts. However we dont observe anything resembling a swarm and its hard to see anything locust-like in a labyrinth-dwelling minotaur. It is hard to understand how they would be an interplanetary threat. An entire species whose ecology is predicated on the successful con of one space traveling individual doesnt make sense. It works as a dramatic devise but it seems like nonsense to me.
The plot was not particularly imaginative since human sacrifice, elaborate cons to set up an invasion, and megalomaniac leaders are common Doctor Who plot devises, but the story was sufficiently interesting and paced to carry a four part story. For me it is one of the weaker examples of Doctor Who but a fun camp romp. From the perspective of an 8 year old it works. In her words the story was cool.
** out of 4