Spectrum mounts an raid on the headquarters of Vulcan Industries. Colonel White confronts the board of governors over their recent breach of the Martian Exclusion Directive: despite the fact that the company's durinium mining operation on Syrtis Major was suspended some time ago, a three-man maintenance team recently left for Mars. On learning that all contact with these engineers has since been lost, Colonel White sends Captain Scarlet, Captain Blue, Captain Ochre, Destiny Angel and Doctor Gold to investigate.