Charles Beaulieu, a playboy writer, is seduced by Gertrud, a beautiful young woman who tells him that she is the wife of Sphax, a prominent art publisher. Shortly afterwards, Charles is approached by a former colleague, Commander Rhome of the Secret Service, who asks him to keep Sphax under surveillance. Rhome tells Charles that Sphax is a Communist agent planning to abduct Banck, a French nuclear scientist, and take him to China. Gertrud creates doubt in Charles's mind, however, when she tells him that he has been duped by Rhome, who actually intends to have the scientist assassinated. Charles locates Banck at the Heidelberg airport; Rhome then attempts to kill Banck but falls victim to one of Sphax's gunmen. Now convinced of Charles's sincerity, Banck turns himself over to Charles for protection.
Source : tcm.com