Another procedural middle episode, which is mainly successful for postponing the climax for another week. The only surprises here are vaguely irrelevant details, like the miniaturisation of the Chameleon’s kidnap victims (discovered in a filing cabinet), with the only big reveal the reason for the Chameleons’ plan: a huge explosion on their home planet wiped their identities, and they plan to abduct 50,000 young people to ensure their survival.

Much of the episode’s run time relies on people restating what has already happened, or is already known. The Commandant’s incredulity is starting to become absurd, as he bleats about getting ‘a solid piece of evidence’ (as if the alien freeze ray wasn’t enough). The Doctor again “outs” Meadows, three episodes after he originally did it, to again establish that the medical centre is wrapped up in the Chameleon plan.

Jamie’s trip on board the Chameleon Tours flight hasn’t exactly advanced the story – he’s now been captured and is feeding the Chameleons, via their duplicate of Inspector Crossland, information about the Doctor. This at least ups the stakes, and leads to the Doctor’s sad realisation that all his friends are now in the clutches of the enemy: ‘First Polly, then Ben, now Jamie’. But bizarrely, rather than joining forces with Samantha to accompany him into space for the final showdown, he picks the restored Nurse Pinto. Perhaps he’s decided Sam isn’t companion material after all.

Next episode: The Faceless Ones – Episode 6