Robert Donat plays Captain Terence Stevenson, a British spy who is sent to infiltrate and destory a German chemical weapons plant in Czechoslovakia during World War II. To do this he assumes the role of Jan Tartu, a member of the Romanian Iron Guard who is both a dandy and a ladies' man. The first order of business is to make contact with the Czech resistance and convince them that he (as Tartu) is on their side. It's a dangerous game all around and Stevenson seldom knows whom to trust. Also known as Sabotage Agent, this film is an ambitious and thrilling flick with stellar performances by Donat and Valerie Hobson (playing the beautiful Resistance fighter posing as a Nazi). Also adding to flick are excellent performances by Glynis Johns and Walter Rilla.
Directed by Harold Bucquet (best known for directing nine of the Dr. Kildare movies), with a script by John Lee Mahin (Quo Vadis, Showboat, The Bad Seed) and Howard Emmett Rogers (Calling Bulldog Drummond, Assignment in Brittany, Tarzan and His Mate) from a story by John C. Higgins (Shield for Murder, He Walked by Night, Robinson Crusoe on Mars), this one is a must-see.