Sellick

Mr. Sellick was headmaster at Brendon Public School.

Biography
Following the car crash involving Vislor Turlough and Ibbotson in Brigadier Lethbridge-Stewart's vintage car, Mr. Sellick told Ibbotson — who Turlough had framed as being responsible for the joyride — that he would be writing to Ibbotson's parents.

When discussing the matter with the Brigadier, Mr. Sellick revealed that Turlough's parents were dead, and his affairs were dealt with by an eccentric solicitor in London.

The Black Guardian appeared in the form of Mr. Sellick during Turlough's dreams while he was sleeping in the school's sick bay, where he tricked Turlough into revealing his intentions. (TV: Mawdryn Undead)

Behind the scenes

 * Mr. Sellick was never named on-screen, and Angus MacKay's credit on parts one and two reads only "Headmaster". His name was given only in Peter Grimwade's novelisation of the story.