Dr. Magnus, a celebrated London brain surgeon is killed by Captain Black on his way home, just as the Mysterons threaten to 'kill time'. Captain Magenta reads in a newspaper that General Tiempo is due to undergo brain surgery in London, and explains to Colonel White that 'Tiempo' means 'time' in Spanish.
Captain Scarlet, on assignment in London, escorts Tiempo and Dr. Magnus to Cloudbase. Magnus insists on continuing wth the operation and his assistant, Dr. Turner and the cerebral pulsator he requires are brought to Cloudbase. X-rays are taken beforehand, and Turner realises that Magnus is a Mysteron when one X-ray, where Magnus' hand was in shot shows the whole hand, not just the bones. Unfortunatly, Magnus in not stopped in time, but Dr. Fawn reveals that he has killed Captain Scarlet, not General Tiempo.
In the confusion, Magnus escapes and locks himself in the generator room. Captain Blue enters through a maintenance hatch and Magnus ends up being electrocuted, which kills him permanently.