A series of horrific murders is traced to a creature that inhabits a very strange house.
Gig Young ... Mike Kelton
Carol Lynley ... Susannah Whately Kelton / Sarah
Oliver Reed ... Ethan
Flora Robson ... Aunt Agatha
Judith Arthy ... Emma
Rick Jones ... Luther Whately
Ann Bell ... Mary Whately, Susannah's Mother
William Devlin ... Zebulon Whately
Charles Lloyd Pack ... Barge Master
Bernard Kay ... Tait
Celia Hewitt ... Aunt Sarah
Robert Cawdron ... John Whately, Susannah's Father
Murray Evans ... Gang Member
Cliff Diggins ... Gang Member (as Clifford Diggins)
Peter Porteous ... Gang Member
Anita Anderson ... Susannah as a Child
Donald Sutherland ... Zebulon (voice)
Ingrid Bower ... Village Girl
Directed by David Greene