Several murders of nuclear scientists, that baffles Scotland Yard, occur in London about the same time that Bill Locklin, a special officer from the United States State Department, arrives to oversee the transfer of Professor Leon Dushenko, a Russian scientist who as fled the U.S.S.R. An attempt is made on Dushenko's life with a monkey's paw-print found at the scene.
Richard Conte
as Bill Locklin
Rona Anderson
as Julia Jackson
Russell Napier
as Supt. John Harrington
Sylva Langová
as Hilde Heller, chief spy
Colin Gordon
as Harry Martin - reporter
Donald Bisset
as Editor Harris
John King-Kelly
as Spy Henchman
Bernard Rebel
as Vinson - Spy Henchman
Arnold Marlé
as Prof. Leon Dushenko
John Horsley
as Det. Sgt. Gibson
Jane Welsh
as Supt. McCollum - sanitarium
Aimée Delamain
as Mrs. Henley
