Boris Karloff

Dr. Henryk Savaard

Lorna Gray

Janet Savaard

Robert Wilcox

'Scoop' Foley

Roger Pryor

District Attorney Drake

Don Beddoe

Lieutenant Shane

Ann Doran

Betty Crawford

Joe De Stefani

Dr. Stoddard

Charles Trowbridge

Judge Bowman

Byron Foulger

Lang

Dick Curtis

Jury Foreman Clifford Kearney

James Craig

Juror Watkins

John Tyrrell

Juror Sutton

George Anderson

Prison Warden (uncredited)

Stanley Blystone

Prison Guard (uncredited)

Sam Ash

Druggist (uncredited)

Nick Grindé