Sebastian Shaw as Sir James Quentin Derrick De Marney as Captain John Mellish Patricia Roc as Pat Quentin Arthur Hambling as Ginger Brown Meinhart Maur as Karl Zaroff John Turnbull as Inspector Gill Peter Gawthorne as General Bullington André Morell as Klein Charles Oliver as Johnson Jack Vyvian as Sergeant Wells Billy Watts as Fernald Charles Paton as Mr. Gibbs Basil Cunard as Dr. Fairlie Hugh Dempster as Nelson Ian Fleming as Pennington Cameron Hall as Badger Wood Scott Harrold as Ted Blacklock F.B.J. Sharp as Coroner Bill Shine as Bystander at accident Cynthia Stock as Matron Lynn Bari as Carol Northrup Mary Beth Hughes as Jerry Daily Joan Davis as Nellie Henry Wilcoxon as Dr. Hugh Mayberry Robert Lowery as Dr. Stephen Greig Alan Baxter as Mickey Ryan Kay Aldridge as Adelaide Sinclair Helen Ericson as Amy McCall Chick Chandler as Gus Joan Valerie as Vickie Elyse Knox as Marjorie Dorothy Dearing as Linda Herbert Rawlinson as John Crane Kay Linaker as Mrs. John Crane Thomas E. Jackson as Inspector Saunders Richard Lane as Lieutenant Lake Frank Coghlan Jr. as Sammy Jerry Fletcher as Hotel clerk Edward Cooper as Butler