Very much a game of two halves. It's one of the best-looking serials of the 60s, and the regulars are on some of their finest form. The scene where the Doctor and Victoria have an honest talk about loss and grief is something that is very rare in the Classic series, but oh so welcome. This is among the most iconic outings for the Cybermen, ever, their sneakiness and villainy following up on The Moonbase. The opening acts are tense and well-paced.

Then along come episodes three and four, and the pacing seems to go haywire. It also goes without saying that there is some seriously racist crap in this story, especially in the way Tobermann is written. It makes it rather hard to enjoy. On balance, I'd still call it a good story, but it could have been great if it had avoided these things.