Operation Secret

Operation Secret is a 1952 American drama film directed by Lewis Seiler and written by Harold Medford and James R. Webb. The film stars Cornel Wilde, Steve Cochran, Phyllis Thaxter, Karl Malden, Paul Picerni and Lester Matthews. The film was released by Warner Bros. on November 8, 1952. The film is based on the exploits of US Marine Corps Major Peter Ortiz.
Plot.
Peter Forrester (Wilde) is a U.S. Marine fluent in French and German, who has served in the French Foreign Legion. He is working undercover in German-occupied France during World War II. After the war, he stands accused of the murder of a Maquis officer at a hearing of the French secret police. Much of the film is told in flashback. One of his accusers, a Communist, is the actual culprit. 
Critical reception.
"New York Times" critic Bosley Crowther said the film "spins its story vigorously but with little impact. This dissipation of potential tension may be attributed to the fact that the self-effacing bravery displayed here has been in evidence on film before, and with greater effect." Crowther said that even though it was based on fact, "this annal of dedicated men braving dangerous assignments appears to be largely hackneyed deeds out of an old and not too thrilling history."
A "New York Daily News" critic observed that earlier films about the underground in Europe had presented all the fighters as "heroes and patriots." but that "now, apparently, it can be told that some of the leaders of resistance movements were fighting first for Russia and only incidentally for their native lands." She praised Wilde for an "effective performance."