Petra Williams was Professor Eric Stahlman's assistant at the Inferno Project.
Biography[]
Petra was at first loyal to her employer, but Greg Sutton helped her realise how dangerous the project really was, and she helped the Third Doctor put an end to it. (TV: Inferno)
Following the shutdown of the Inferno Project, she and Greg became lovers and planned to leave Great Britain in February 1970. When James Stevens attempted to meet with Greg to talk to him about the events at Eastchester, Petra tried to stall him in order to not delay their departure but this was to no avail. (PROSE: Who Killed Kennedy)
The Doctor and Ian Chesterton attended Greg and Petra's wedding. (PROSE: The Devil Goblins from Neptune)