Stevenson, a British soldier fluent in Rumanian and German, goes undercover to sabotage a German poison-gas factory. He turns himself into Jan Tartu, a member of the Rumanian Iron Guard. But when his contacts are destroyed, his cover may get him killed by the very underground he needs to succeed.
Robert Donat - Captain Terence Stevenson, aka Jan Tartu
Valerie Hobson - Maruschuka Lanova
Walter Rilla - Inspector Otto Vogel
Glynis Johns - Paula Palacek