Sarah and Bert search the mines, whilst The Doctor and Brigadier go in search of equipment to rescue them.
It's a solid second episode, there's plenty going on including a fight scene for The Doctor, and a big reveal of what's lurking in the mines.
Suspense is a big strength here, it's tantalising, the way in which the story develops, it's what I feel the new series lacks, time to development. Not that long ago, a similar story, Arachnids in the UK was released, so poor compared to this.
There is such a richness and depth to the characters, Bert for example, it's a lovely performance from Roy Evans, and all the cast.
Jon's fight scene is fun, although they could have matched the stunt man's hair up a bit better, the wig is a bit dark and ill fitting. The scenes in the mine look awesome, and those maggots are a real triumph.
More questions asked, what's that green one, and just who is The Boss?
Classic. 9/10