Anne Heywood as Anna Holt

Peter van Eyck as Dr. Peter Corrie

Cecil Parker as Stevenson

Bernard Lee as Dr. Frank Shears

Ellen Schwiers as Ella

Siegfried Lowitz as Mr. Walters

Hans Nielsen as Immerman

Jeremy Spenser as Martin Holt

Maxine Audley as Marion Fane

Jack MacGowran as Furber

Miles Malleson as Dr. Miller

George A. Cooper as Thomas Gabler

Dieter Borsche as Dr. Miller

Ann Sears as Stevenson's secretary

Irene Richmond as Mrs. Gabler

Allan Cuthbertson as Da Silva

Bandana Das Gupta as Miss Soong

Alister Williamson as Inspector Pike

Patsy Rowlands as Young Woman at Dance Hall (uncredited)

Bryan Pringle as Dance Hall MC (uncredited)