The Doctor and Jamie tell the Brigadier about the Cybermen but with Rutledge under Vaughn's control he is powerless to act.
Quest roles:
Nicholas Courtney(Brig. Lethbridge-Stewart), Peter Hawkins(Dalek (voice)), Kevin Stoney(Tobias Vaughn), John Levene(Sergeant Benton), Sheila Dunn(Petra Williams), Sally Faulkner(Isobel Watkins), Peter Halliday(Soldier), Ian Fairbairn(Doctor Chester), Edward Dentith(Major-General Rutlidge), James Thornhill(Sergeant Walters), Robert Sidaway(Captain Turner), Dominic Allan(Policeman), Peter Thompson(Primord)