When the TARDIS lands in a quarry on Earth, Sarah unearths what appears to be a fossilised hand, buried in one-hundred-fifty-million-year-old strata. Analysis shows the hand to be silicon-based and inert, but when Sarah begins to act as if possessed, the Doctor suspects that it may still be alive...
Tom Baker
The Doctor
Elisabeth Sladen
Sarah Jane Smith
Stephen Thorne
Kastrian Eldrad
Judith Paris
Eldrad (female form)
Roy Pattison
Zazzka
Roy Skelton
King Rokon
Rex Robinson
Dr. Carter
Glyn Houston
Professor Watson
