Butler (Invasion of the Dinosaurs)

Butler was an assistant to Sir Charles Grover and Professor Whitaker during Operation Golden Age.

Biography
Butler also narrated the propaganda film watched by Sarah Jane Smith in the reminder room aboard the fake spaceship.

He was knocked out by the Third Doctor and arrested by UNIT when they raided their bunker. (TV: Invasion of the Dinosaurs)

Behind the scenes

 * Butler has never been identified with a first name, either in Invasion of the Dinosaurs or any spin-off media.
 * In Malcolm Hulke's novelisation of the story, but not in the televised version, Butler had a scar on his left cheek from when he was a firefighter, caused by a facial injury sustained by having fallen through a plate glass roof after having rescued and passed to safety a child who had crawled out onto a high ledge.