Bret Vyon was a Space Security Agent who assisted the Doctor in his quest to stop the Daleks from conquering the Solar System
Profile
Early Life
Bret was born in Mars Colony 16.
Service
In 3990 he joined the Service, made First Rank in 3995 and Second Rank in 3998. His sister, Sara Kingdom, would also join the Service.
Fight against the Daleks
Posted on a mission to Kembel in 4000 with another agent, Kert Gantry to investgate suspicious activity on the part of Mavic Chen, Guardian of the Solar System. Suffering a similar fate to Marc Cory, Bret was saved by meeting the Doctor, who had also discovered Cory's tape-recording. Bret thus learned that Chen had allied himself with the Daleks.
Bret stole Chen's Spar and took the Doctor, Steven, and Katarina with him in it to reach Earth in time to warn of Chen's plot. Chen had by this time convinced Bret's sister, Sara Kingdom, that he was a traitor and she killed him. Once Sara learned the truth, Sara allied herself with the Doctor to save Earth and avenge his death. (DW: The Daleks' Master Plan)