Maximum security is imposed at London International Airport, from which the Director General is due to leave the country. At the request of Colonel White (voiced by Donald Gray), the resurrected Mysteron double of Captain Scarlet (voiced by Francis Matthews) – whom Dr Fawn (voiced by Charles Tingwell) has determined to be free of Mysteron control and effectively "indestructible" after the Mysterons' failure to assassinate the World President – returns to duty to help lead the operation. Accompanied by the Angel fighter squadron, Scarlet and Captain Blue (voiced by Ed Bishop) depart Cloudbase in a Spectrum Passenger Jet and fly to London.