Sarah Jane travels to
Antarctica to visit Will Sullivan, Harry Sullivan's brother, and his science research team — unaware that one of the team is a murderer. The Crimson Chapter are secretly using the Antarctic base as a front for their fundraising activities, and the Keeper is manipulating events to lure Sarah Jane to a lonely spot in order to ensure her death.
Tom Chadbon, in addition to appearing in the Doctor Who serial City of Death with Tom Baker, also appeared in the Colin Baker television serial The Mysterious Planet (episodes 1 to 4 of The Trial of a Time Lord) in 1986. For Big Finish, Chadbon has also appeared with 8th Doctor Paul McGann, during The Eighth Doctor Adventures (2007), in the serial No More Lies. His science fiction credits include appearing in the BBC tv series
Blake's 7, as Del Grant in the series 2 episode Countdown. He is also famous for playing Sandra's husband in the long running BBC situation comedy
The Liver Birds.
David Gooderson has extensive acting credits in television and radio going back forty years. He has twice been a member of the BBC Radio Drama Company, and has made over four hundred broadcasts. His science fiction credits outside Doctor Who include appearing in two cult radio shows: playing Tidy, the sentient android, in series 2 of
Earthsearch; and the barman in
The Hitchhiker's Guide to the Galaxy.
Jacqueline Pearce appeared in Doctor Who with Colin Baker and Patrick Troughton, in the tv serial The Two Doctors. Her science fiction credits include appearing in the BBC tv series
Blake's 7 from 1978 to 1981, as series regular Supreme Commander Servalan.
Stephen Greif's science fiction credits include appearing in the BBC tv series
Blake's 7 in 1978, as series regular Space Commander Travis.