Based on Martin Flavin’s play, a young man accidentally kills a man in a fight and goes to prison where a cellmate of his is intent on getting revenge against one of the guards. The man who prosecuted the young man becomes the prison warden, and his daughter falls in love with the young man.
At the precinct office of a police station two men argue over the scoring of a double pinochle, and one keeps saying the other owes him 42 cents. They go out to answer a call using a siren. They go into a nightclub, and the doctor says he may pull through. He was hit by a water bottle, and he points to Robert Graham (Phillips Holmes) as the man who did it. They question him and his girlfriend, Gertrude Williams (Mary Doran). The two men take them in their car to the office of the district attorney, Mark Brady (Walter Huston). He tells Gertrude to sit down and has her lower her skirt. He asks her what happened. She says she never saw the young man before. She went with him to a place to dance. He asks her if she has seen the water bottle, and she admits she has. She admits they had some gin and that it was her idea. She says Mr. Parker got fresh with her on the floor. She admits she knew him. She says he wanted her to go to her table, and he got sore. She says he reached back into his hip pocket, and then the boy hit him with the water bottle. Brady tells her to come back at five and not talk to anyone.
Gertrude leaves, and Graham sees her go. Brady answers the phone and tells the press he will give them a statement later. He has his assistant bring the boy in. Graham comes in. Brady on the phone says he is taking charge of the case and that he will be lucky if he does not hang. He questions Graham and calls him “Bob.” Graham says he turned twenty yesterday. He was working for a broker, and he was never arrested before. Brady says he is in a jam because Parker died. Brady offers him a drink, but Graham says no. Graham says his firm sent a lawyer to him who told him not to talk. Brady agrees with that and tells him he had tough luck. Graham goes out. Brady tells his assistant he has a good personality, and a good defense attorney could make it difficult for them. Brady says he would get him off. A police officer comes in and says Leonard Nettleford (Arthur Hoyt) is there, and Brady asks him to come in. Nettleford enters and tells Brady he is a lawyer for the stock broker. Brady frankly tells him it is an open-and-shut case. He says seven eye witnesses saw Graham kill Parker, and they are going to ask for a verdict of second-degree murder. Nettleford says he has not consulted the criminal code in twenty years. Nettleford says it was an accident, and Graham is sorry. Brady says if he pleads guilty, the maximum sentence will be ten years. Brady says somebody has got to pay, an eye for an eye.
In court the judge sentences Robert Graham to ten years in prison. Nettleford tells Graham he is sorry. Graham is taken away. Nettleford thanks Brady for his courtesy, and they say goodbye.
In prison the inmates march to their cells. Years pass. Cell doors open, and the men go in. Then the doors close. Two officers are making the count. Graham says they are locking up the animals for the night. Graham says he has counted the hours in six years, and he has four more years. He wishes he could sleep for a year. Jim Fales (Otto Hoffman) asks him to play checkers and says he is going to break out soon. Graham asks him to take him with him. Ned Galloway (Boris Karloff) says eight of nine come back on a stretcher. Graham says he wants one good meal and to see a woman’s face. Jim asks Galloway, who says he has an appointment with a guy. He was sentenced to twenty years. He got out after eight, had a glass of beer, and was turned in to do his last twelve years. He says the man who turned him in is in the prison. An officer delivers a telegram. Graham reads it, and then the others read it. Jim tells Graham it is his move. Graham says his mother used to come see him every Friday. He says she wanted to live with him there. He says his getting a rotten deal killed her. Graham says he has to get out, and he disrupts the checker game. He starts shouting, and the others try to restrain him. He gets quiet before the Yard Captain Gleason (DeWitt Jennings) arrives. Jim says it was him, and Galloway asks him to come in. Gleason warns them to keep quiet, or they will go to the hole. Gleason walks away. Jim asks Galloway why he is does not like that fellow, and Galloway says he is the one he has the appointment with. Graham asks if he yammered, and they say he did. A bell rings, and the lights go low.
A newspaper reports that Brady has been made the prison warden. Gleason asks what kind of warden he will be. Many men were sent to prison by Brady. Graham is sleeping on the floor and says he may be warden as well as any.
Gleason is told to report to the new warden. McManus (John Sheehan) introduces Gleason to Brady, his new boss, as the best yard captain in the prison system. Brady introduces his daughter Mary (Constance Cummings) and his housekeeper, Katie Ryan (Ethel Wales). McManus points out the 2,552 men in the yard below. McManus estimates that Brady sent up about a thousand of them. Some men look up at their windows and start yelling. Other prisoners join in the yammering. Gleason says they do that when they are sore. Brady wants to go down, but McManus advises him to stay up there. McManus suggests he let Gleason go. Brady says it is his job to be warden, and he goes down alone. McManus sends Gleason down.
Brady comes out of a door into the yard and lights a cigar. He goes down stairs and walks among the men, who become quiet. Brady says hello to one man and walks past the others. Gleason tells them to break it up and blows a whistle. The men line up, and a whistle commands them to march away.
Graham is working in the jute factory. An officer blows a whistle, and they stop the machines. Graham keeps hearing them in his brain and becomes hysterical and faints. An officer has him carried out.
Dr. Rinewulf (John St. Polis) asks Graham where he works and says he can go. Graham walks away slowly.
Dr. Rinewulf tells Brady that Graham is not a criminal, and he is worth saving, though he is almost gone. Brady agrees to see him.
Gleason brings Graham to Brady, who calls him Bob again. Graham remembers Brady, and Gleason reminds Brady it is the Parker case. Mary comes in and says they are having tea. Graham looks at her, and she goes out. Brady asks if he ever drove a car, and Graham says yes.
Mary comes in and asks the doctor about Katy. He says the prison depresses her. Dr. Rinewulf says she has reconstructed the man who drives her father’s car. Graham comes in with the groceries and asks Mary what to do with them. She sends him to the kitchen. The doctor asks her if he is mended, asking her to look into his eyes. He leaves, and she goes into the kitchen. She asks him to peel potatoes for her. They talk about baseball, and she says she could have driven the car. He says driving the car may help him later. He asks if it will make a difference that he has been in prison. He asks if it matters to her, and she says no. She offers to finish the potatoes and asks him to give her handkerchief back. He hesitates and then hands it to her.
In their cell Jim asks Graham if he is ready to make the break tomorrow night, and Graham says no. Galloway asks who else is involved, and Jim says Runch is one; but Galloway says he is a stool pigeon.
The next night Jim and another man are caught by a wall, and Jim is shot.
Brady is being shaved by an inmate and is reminded that he sent him up for cutting a man’s throat. McManus comes in and says Brady is a hero now. Brady has the barber leave. McManus asks Brady what he did with Runch who squealed. Brady says they have got to get him out of there before he is killed. McManus suggests that he get rid of Mary for a while, and he says he will. Brady asks him to bring him a safety razor.
In the kitchen Galloway tells Graham that Jim liked him and that someone is going to get Runch. Galloway advises him to stay away from Runch. Outside Graham and Mary wait at a railway station, and they talk. She asks if he is bitter, and he says he is not anymore. She says her father is trying to get her parole. He says it does not matter if she stays. He would like to see her every day. The train arrives, and he gives her suitcase to a porter and says goodbye to her as she boards the train.
At 2 p.m. men line up in the yard and then relax. In the office Gleason tells Brady that trouble is brewing. They watch the men from the window and see them gang up. Brady orders him to get machine guns ready. In the yard a man passes the message “Runch 2:15.” In his office Brady tells Runch (Clark Marshall) to put some papers away. He asks why he is so nervous. Runch is afraid they will get him. Runch begs Brady to get him out of there, and Brady says he is doing what he can. Graham comes in, and Brady dismisses Runch, who goes out.
Galloway brings tea to Katie, and she objects to his being so quiet.
At 2:11 men begin yammering in their cells. Others are in the yard. Brady tells Graham to stay there until he comes back. Katy is asleep, and Galloway changes her tea cup. Runch asks Graham why they are yammering. Runch asks if they are going to get him and cries. Runch asks Graham to go out and get the guards, begging. Graham goes out. The inmates are yelling in various places. Runch looks out the window nervously. Galloway comes in quietly with a knife, and Runch turns and sees him. Galloway corners Runch in a small room and closes the door.
At 2:16 Graham sees Galloway come out of the room. Galloway tells him to get out. Graham goes in the room and reacts by backing away. Galloway asks Katie if she wants more tea, and she says no.
Brady and Gleason come back in. Gleason says they may pull a stunt to cover up something. Brady goes in the room and says Runch is dead. Brady sees Graham and asks him who did it. Graham says he does not know. Brady goes and asks Katie if she saw anyone. Gleason says they did not see anyone come or go. Brady says someone could have used the stairs. Brady asks Graham who did it. Brady says he is lying and asks him what he will tell the inquest. Brady says he knows he did not do it, but they may hang it on him. Graham says he will not squeal; he would rather die. Brady says he will not be able to keep him there. He will have to go back to the jute mill. Brady asks who killed the man. Brady asks which way he came. Graham says he does not know. Brady says he wants to help him. Brady says he will be blamed because of the election coming. Brady says he is giving up his life for a code of the criminals. Graham says their code is right for them, and he cannot go back on it. He would be like Runch. Gleason comes back in and says he found nothing. Brady offers Graham parole if he will talk. He threatens him with a dark dungeon. Graham says nothing, and Brady tells Gleason to lock him up. Gleason suggests bread and water in the dark for a week. They go out, and Brady calls for the coroner.
Gleason visits Graham in his dark cell after a week. He tells him to get up, and Graham stands up. Gleason gives him a cigarette, but his only match goes out. Gleason talks about the dinner they had. Two officers outside say Gleason is going too far. Gleason says he has a parole waiting for him; he could be out in an hour. He asks who killed Runch, and Graham says he does not know. Gleason knocks him down and has him locked up.
The state attorney complains to Brady that this murder has not been solved. No inquest has been held. He says the code is an eye for an eye, and Brady must do something. Brady says he will do nothing. Brady lectures the young man and says he is working on the case. He warns him not to indict an innocent boy. The state attorney says he will report Brady and call for an inquest.
Cluck (Andy Devine) puts a knife in the food bucket for Graham, and the man says he will not tote any knife. Cluck says the kid deserves a break, and the knife is a two-way out, either him or Gleason. The man carries the bucket to the hole and puts it in Graham’s cell.
Brady welcomes his daughter Mary back. She asks what he has done with Graham. Brady says he will come out all right. She says she is worried about Graham, not her father. He admits Graham is in the dungeon for shielding a murderer and to save his life. She says he is a clean and fine boy. Brady says his parole is there, but his hands are tied. She says she would set him free. He deserves a chance. Brady says they would bust him. Brady says he is not God; he has done the best he could. The law must take its course. She pleads, and he asks why she is so upset. She cries, and they embrace. She says she loves him. She is sorry if it hurts him. He says she knows what she is doing. He says he will turn demons out of hell for her. He says he will never serve another day. Brady sends for Gleason to bring up Graham. Brady tells Mary they will get him out.
The man tells Galloway that Cluck sent a knife to Graham and that Gleason is going down to get the kid. Galloway says he will keep his appointment. He sees Gleason and says he does not like him. He spits on Gleason, who raises his club. Another officer helps him capture Galloway.
Brady tells Mary it is tough waiting. They hear a siren. Brady goes down stairs. In the dungeon an officer shoots at Galloway, who is behind a wall. Brady arrives, and Gleason tells him what happened. Brady threatens Galloway with tear gas. Galloway has a knife and throws the gun out, saying he trusts Brady. He comes out with his hands up. Brady tells Gleason to take care of him. Galloway grabs Gleason and holds the knife on him. Galloway admits he got Runch. Galloway calls Gleason a squealer, and he stabs him. An officer then shoots Galloway dead.
Brady brings Graham in to Mary. Graham sits down as she puts her arms around him. She tells her father that she is happy. He says things break that way sometimes.
This prison drama portrays the harsh criminal code that punishes people in prison and the code of the criminals that keeps them from squealing. A woman sees past the crime a young man committed and realizes he is a good man. The district attorney who becomes the warden enforces the law of retribution; but he is glad the young man gets a break after not doing any more harm.