Trivia / Doctor Who S5 E1 "The Tomb of the Cybermen"
Fake American: Vienna-born George Roubicek and Welshman Clive Merrison play Captain Hopper and Jim Callum. Their accents are quite awful.
Missing Episode: Averted. Like the rest of Season 5 (and Season 4), this story was lost for decades... until 1991, when a copy of all four episodes was returned from Hong Kong of all places, along with a number of other old British TV programs. It would remain the only intact serial from Patrick Troughton's first two years until October 2013, when the discovery at a relay station in Nigeria of nine more lost episodes, all from Season 5, led to the completion of The Enemy of the World (only one of its six episodes was known to exist before this).
Real-Life Relative: Shirley Cooklin (Kaftan) was married to producer Peter Bryant. Fraser Hines actually flirted with her, not realising that she was his boss' wife.
Throw It In!: Patrick Troughton and Frazer Hines came up with the gag of the Doctor and Jamie holding each other's hands themselves. They did so without the director's knowledge, so that he'd have no choice but to leave it in.
When Victoria asks the Doctor what a Cybermat is, he points to a book and says, "One of those". This was an ab-lib by Troughton when he forgot his line.
What Could Have Been: Toberman was originally intended to be deaf, hence his lack of significant speech; his hearing aid would foreshadow his transformation into a Cyberman. These elements were included in the novelisation.