This really long story wraps up after a pretty small and very well-staged shootout between the UNIT troops and some badly over-matched Cybermen. Subsequent adventures would see the humans outclassed and often on the losing end of alien firepower, but not here. It also sees John Levene’s character of Corporal Benton taking a larger role, apparently because the fellow who had played Sgt. Walters had got on director Douglas Camfield’s bad side. Benton would reappear a few episodes into the next season, and remain a semi-regular into season thirteen.
Our son really enjoyed this story, and it’s clearly one of his favorite Doctor Who adventures. He let us know, in his inimitable five year-old way, that his favorite moment was when the missile destroys the main Cyberman ship. He demonstrated this by rolling on his side and explaining that his foot was the Cybership, and his hand the missile. He slapped them together and thundered “Ka-BOOM!”