Several murders of nuclear scientists, that baffles Scotland Yard, occur in London around 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 has fled the USSR. An attempt on Dushenko's life is made with a monkey's paw-print found at the scene.
as Bill Locklin
as Julia Jackson
as Supt. John Harrington
as Hilde Heller, chief spy
as Harry Martin - reporter
as Editor Harris
as Spy Henchman
as Vinson - Spy Henchman
as Prof. Leon Dushenko
as Det. Sgt. Gibson
as Supt. McCollum - sanitarium
as Mrs. Henley
