Dirk Bogarde as Dr. Simon Sparrow

Samantha Eggar as Delia Mallory

James Robertson Justice as Sir Lancelot Spratt

Donald Houston as Major Tommy Ffrench

Barbara Murray as Iris Merchant

Dennis Price as Dr. Blacker

Mylène Demongeot as Sonja Stromberg / Helga Stromberg

Jill Adams as Genevieve Milton

Timothy Bateson as Mr. Holly

Jessie Evans as Mrs. Parry

Fenella Fielding as Passenger on Train

Frank Finlay as Corsetiere

Derek Fowlds as Gillibrand

Michael Flanders as Mr. Bradby

Pauline Jameson as Ward Sister Bond

Bill Kerr as Australian Sailor

Ann Lynn as Mrs. Mary Whittaker

Joe Robinson as Sonja's Boyfriend

Madge Ryan as Mrs. Clapper

David Weston as Stuart

Paul Whitsun-Jones as Grimes

Ronnie Barker as Man at Railway Station Ticket Counter (uncredited)

Amanda Barrie as Miss Rona Steele (uncredited)

Reginald Beckwith as Meyer (uncredited)

Christopher Beeny as Medical Student (uncredited)

Margaret Boyd as Lady Willoughby (uncredited)

John Bluthal as Railway Porter (uncredited)

Richard Briers as Medical Student (uncredited)

Johnny Briggs as Medical Student (uncredited)

Victor Brooks as Police Constable (uncredited)

Peter Butterworth as Ambulance Driver (uncredited)

Rodney Cardiff as Student Doctor (uncredited)

Pauline Chamberlain as Nurse (uncredited)

Denise Coffey as Food Seller at Railway Station (uncredited)

Victor Croxford as Hospital Porter (uncredited)

Alistair Dick as Train Passenger (uncredited)

Felix Felton as Health Farm Patient (uncredited)

Hilda Fenemore as Railway Station Barmaid (uncredited)

Michael Goldie as Physical Training Instructor (uncredited)

Richard Gordon as George Stubbins (uncredited)

Barbara Hicks as Miss Minton (uncredited)

George Hilsdon as Police Constable (uncredited)

Douglas Ives as Mr. Lewis (uncredited)

Juba Kennerley as Passerby (uncredited)

Ronald Lacey as Mum's Diner Customer (uncredited)

Harry Landis as Mum's Diner Customer (uncredited)

Jeanette Landis as Rosie (uncredited)

Aileen Lewis as Train Passenger (uncredited)

Leo McKern as Mr. Harry "Luther" Heilbronn (uncredited)

Jill Mai Meredith as Health Farm Nurse (uncredited)

Richard Neller as Council Official (uncredited)

Robert Rietti as Various (voice) (uncredited)

Renu Setna as Indian Medical Student (uncredited)

George Spence as Health Farm Patient (uncredited)

Ronnie Stevens as Hotel Manager (uncredited)

Marianne Stone as Mum's Diner Waitress (uncredited)

Toke Townley as Clerk of Works (uncredited)

Paula Wright as Train Passenger (uncredited)