Arnold Jellicoe was a member of the Scientific Reform Society and Hilda Winters' assistant. He was assigned to adjust the K1 robot's prime directive to enable it to kill. (TV: Robot)
Jellicoe was arrested after the SRS was broken up by UNIT. Jellicoe had died in prison sometime before 2002, after Winters had already been released.
Jellicoe also had a daughter or niece, named Wendy Jennings, who worked alongside Winters in order to exact revenge on Sarah Jane Smith. (AUDIO: Mirror, Signal, Manoeuvre)