People in an old, dark mansion are menaced by a maniac called "The Black Ace".

Chester Morris
as Neil Broderick

Vivienne Osborne
as Martha Winters

Frank McHugh
as Clancy

Allen Jenkins
as Dugan

Henry Stephenson
as Thornton Drake

Grant Mitchell
as Austin Winters

Charles Middleton
as Jerry Simons

Virginia Howell
as Mrs. Quincy

Oscar Apfel
as Asa Marsden

Cornelius Keefe
as Henderson
CinemaSerf
This is a rather basic crime drama that showcases the talents of Frank McHugh ("Clancy") and Allan Jenkins ("Duggan") as a couple of detectives called to a big house to investigate the murderous shenanigans of the "Black Ace". The mysterious killer has a habit of impaling his victims and he wants th...