Special Guest Stars Edward Mulhare as Professor Mathers Guest Stars David McCallum as Gwyllim Griffiths Nora Marlowe as Mrs. Ives George Pelling as Policeman Robert Doyle as Wilt Morgan Jill Haworth as Cathy Evans Constance Cavendish as Gert "the Bread" Evans Uncredited Janos Prohaska as Darwin the Monkey
