Joseph Cotten adapted Eric Ambler's novel about an American armaments agent trying to escape from a Nazi-paid assassin in Turkey.
In Istanbul assertive Kopeikin (Everett Sloane) gets Howard Graham (Joseph Cotten) to leave his wife Stephanie Graham (Ruth Warwick) to go out to a nightclub, where he meets dancer Josette (Dolores del Rio). A magician is shot dead. Howard says it was meant for him, because he sells arms. Howard is questioned before Col. Haki (Orson Welles), who says Peter Banat is trying to kill him for the Nazi Mueller. Col. Haki lets Josette and Gogo (Jack Durant) use his car and tells Howard he must go with them on the boat for his safety. Kopeikin gives Howard a gun, which he hides in his cabin. Howard meets the Turk Kuvetli (Edgar Barrier), who sells tobacco, and Dr. Haller (Eustace Wyatt), who says he is an archaeologist.
At a dinner table Howard sees Peter Banat (Jack Moss) and asks the captain to put him ashore, because Banat wants to murder him. Matthews (Frank Readick) tells Howard how he became a socialist to manipulate his wife (Agnes Moorhead), but he came to believe in it. Howard can't find his gun and sees Banat in the hall. Howard finds Josette and tells her Banat was hired to kill him. She says she will get Gogo to play cards with Banat. Howard goes to Banat's cabin and searches but finds that Dr. Haller with a gun is Mueller, who says Howard must be killed or be delayed by going to a typhus hospital. Kuvetli is there to protect him and tells Howard to accept Mueller's proposal, and at the port he will get Mueller and Banat arrested. Howard asks Mathews to take a message to the Turkish consul and asks if he has a gun. Mathews gives him a knife.
Howard gets off the boat and goes with Mueller and Banat in a car, which gets a flat tire. Howard jams the horn with the knife and escapes. In a hotel he joins his wife Stephanie and finds Mueller there using another name. Banat keeps Howard from leaving. Mueller sends Stephanie to Col. Haki. Howard gets a call from Josette and escapes from Banat out the window. Banat shoots at Gogo, who reports it. Mueller is shot by Col. Haki, who warns Howard and is shot by Banat on the ledge. Banat runs out of bullets, and Howard pushes him off the ledge. In the final scene Howard tells Col. Haki he spent too much time running away.
This spy thriller reflects the violent atmosphere of
the Nazi war in which an American selling arms finds himself in