The Doctor and Leela, having just faced down a crazy zealot with a glove for a helmet, land in a mine. Well, on a mine. Well, on a mining ship...er, mining tank? Anyway, they’re on this giant mining vessel (yes, vessel sounds good) crewed by a small team of humans (who, if we’re being honest, have some of the most wild outfits!) and a much larger team of robots. However, under the surface (it’s a mine gag...the gag is also mine), foul play is afoot as humans start dying off left and right. But who is behind these, ahem, Bad Robots? Can the Doctor and Leela save the day before everyone is marked by the bicycle reflectors of doom?