Barry Letts opened the documentary by explaining that the Cybermen were chosen to be a returning monster as they had always been a favourite, but hadn't been used since Patrick Troughton's tenure. Philip Hinchcliffe's early career was then examined and Letts recalled how he fitted in well with the production team.
Michael E. Briant then explained how, in Wookey Hole Caves where they were filming, a diver had drowned four weeks earlier and people claimed to have seen him since. There was also stalagmite there, nicknamed the witch. The electricians dressed it up in a black cloak with a pointy hat and a broom for a joke. One-and-a-half hours later, the second electrician fell off a rock for no apparent reason and broke his leg. Two hours after that, Elisabeth Sladen was forced to jump from her boat when it went out of control and had to be pulled from the water by the stuntman, who then ended up in hospital.
Following this, Briant expressed how he was worried as to how the Cybermen would cope in such a low-ceilinged cave system and both he and Hinchcliffe considered how they could only work with a handful of costumes where modern CGI allows for huge armies to be created. Briant chose specific weapon sets for each of the factions; the humans had Uzis, the Vogans had flare guns and the Cybermen had inbuilt guns on their heads - an idea Briant claimed to have pioneered.
It ended with Hinchliffe considering how the effects, such as the plague and Kellman's handheld screen, had held up well; even by modern standards.