Guest Stars Lynda Bellingham as The Inquisitor Michael Jayston as The Valeyard Tony Selby as Glitz Joan Sims as Katryca Adam Blackwood as Balazar Glen Murphy as Dibber Tom Chadbon as Merdeen Timothy Walker as Grell David Rodigan as Broken tooth Roger Brierley voices Drathro Sion Tudor Owen as Tandrell Billy McColl as Humker Uncredited Robert Goodman as Crew Member