Red Leader was the leader of Red Squadron in the Royal Air Force during the Battle of Britain in August 1940. In one flight on 27 August, while pursuing the Luftwaffe, Red Leader detected signs of a cloaked Heliyon ship. Despite the base's urgent warnings against his course of action, Red Leader summoned Red Squadron to investigate. Red Squadron was subsequently destroyed by the ship's force field.
Red Leader and his squadron were among many RAF casualties caused by the Heliyon. The recurrence prompted Winston Churchill to call the Doctor for assistance. The Eighth Doctor and Liv Chenka responded. (AUDIO: Their Finest Hour)