Rendezvous

In April 1917, William Gordon is commissioned in the U.S. Army and travels to Washington, D.C. to prepare for deployment to France. The day before departure he spends with socialite Joel Carter, sharing his wish to fight on the front lines rather than behind a desk.

Just before boarding his train, Gordon is ordered to report to the Assistant Secretary of War and is reassigned to the code-breaking room. He is tasked with deciphering an intercepted German message that Major Brennan has failed to crack.

Gordon discovers that Carter is Joel's uncle and that Joel revealed Gordon’s true identity to keep him in Washington. The revelation complicates their relationship and the mission.

To protect convoys, the Allies adopt a new wireless rendezvous code devised by Major Brennan. An ammunition ship is sent to test the system, but doubts arise about the code’s security as it could be compromised.

A German spy ring in the city gains access to Brennan’s code, allowing the test ship to slip by and lure valuable transports into a deadly trap. Gordon deciphers the intercept and realizes the code can no longer be trusted.

Brennan suspects his mistress Olivia Karloff has stolen his code. When confronted, she shoots him in panic and kills him. Her superiors direct her to redirect American attention away from the spy ring.

Although Olivia is under suspicion, Gordon releases her and uses her to lead him to the rest of the spies. Joel grows jealous, thinking Gordon is charmed by Olivia.

Olivia covertly warns Captain Nieterstein that the spy ring will betray him. At a later meal, she drops one of his medals into a glass of water, revealing the reagent and exposing his complicity. The stolen code book is found in his possession and he commits suicide.

Gordon forces Olivia to lead him to the hotel staffed by enemy agents where the spies operate. Joel becomes a hostage; Gordon is captured and forced to pretend he is decoding the convoy’s position.

Under pressure, Gordon gives the spies the coordinates to the hotel instead of the convoy. The spy ring relays the information, but American authorities intercept it just in time.

Justice Department agents storm the hotel and rescue Gordon and Joel. Carter recognizes the hotel's address, interrupting the spies’ plan and turning the tide in Washington.

Gordon resumes his journey toward France, but Joel uses her influence to keep him in Washington. The mission to break the code continues, but the immediate danger has passed.