Adapted from William Joyce Cowan's novel, two men drafted into the world war fall in love with the same nurse but have different values after the war.
Fred Willis (Spencer Tracy) and Jimmy Davis (Franchot Tone) are trained by Sergeant Meadowlark (Edgar Dearing) as soldiers to kill. Jimmy faints, says he was taught not to kill, and decides to leave; but Fred knocks him out. Jimmy finds he likes shooting. In France they fight in the trenches. Jimmy climbs a church steeple and kills Germans until a bomb hits. Fred looks for wounded Jimmy and pesters nurses Rose Duffy (Gladys George) and Saxe (Mary Treen). Fred hides as Rose nurses Jimmy. Fred thanks her for saving Jimmy's life. Fred tells Rose to meet him and is angry when she is late. He kisses her, and she knocks him down. They both apologize and kiss again. Soldiers march, and Fred says good-bye to Rose. Jimmy asks Rose for a kiss good-night and says he loves her. Rose walks Jimmy in a wheelchair, and they learn that Fred is missing.
Recovered Jimmy receives a medal, and Fred takes his picture. Fred tells how he was captured and escaped. Jimmy tells Fred that he is marrying Rose and would die without her. Rose learns that Fred is back and finds him drunk with two women. Rose pulls him out by his hair and says they have to break it to Jimmy; but Fred won't marry her.
After the war Fred sees a murder and then Jimmy, who invites him to visit. Fred meets Sergeant Meadowlark as he is investigating the murder. Fred suspects Jimmy and calls on him. Rose asks Fred about his wife, and he says she died. Jimmy admits to Fred that he is a gangster and says he does it for Rose. Fred tells Jimmy to quit. Fred summons Rose to the circus and blames her for Jimmy's racketeering before he realizes she didn't know. Fred asks her to leave Jimmy. Rose observes Jimmy sending out killers dressed as cops, and she calls the police. Rose visits Jimmy in jail. Jimmy plans to kill Fred for squealing; but Rose says she did it. Jimmy walks away as Rose pleads. In his trial Jimmy's lawyer argues his war experience, but Jimmy declares he is guilty and is sentenced to three years. Jimmy's friends try to take Rose and follow her home; but Fred has circus men to protect her.
In prison Jimmy misses Rose. She works for the circus with Fred, who kisses her good-night; but she reminds him she is Jimmy's wife. Jimmy escapes and steals a car that overturns, killing the other escaping prisoner. Rose and Fred find Jimmy in a circus trailer. Rose tells him to give up; but Jimmy takes the show money and asks Fred to help. Fred says he loves Rose. Jimmy pulls a gun; but Fred reprimands him and takes the gun. As police approach, Fred offers to hide Jimmy; but Jimmy tries to run and is killed. Fred tells Sergeant Meadowlark that he made a soldier out of him.
This drama shows how war training can have unintended consequences on some. Fred tries to persuade Jimmy that violent crime will not work.