A Korean War veteran's morphine addiction wreaks havoc upon his family.
War veteran Johnny Pope, his wife of four years Celia Pope, who is pregnant with their first child, and Johnny's younger brother Polo Pope live together in a working class existence in the inner city of New York. Johnny and Polo have always looked out for each other, which is now made all the more difficult with Polo, unknown to Johnny, being attracted to Celia himself. Uneducated Polo is currently the largest household breadwinner working as a bouncer at a sleazy bar - it the best paying job with his skills - as Johnny, untold to Celia, has lost his latest job, the fourth such in the last three months. Without a word, Johnny often disappears for large periods of time, and although she inherently still loves him, Celia is uncertain if she can stay in a marriage in which he no longer touches her or acknowledges their baby, especially as she believes he is having an affair. She would admit to herself that in her loneliness she often does think about falling into Polo's arms. These issues are exacerbated by the visit of Johnny and Polo's father from Palm Beach, he who they have not seen since before Johnny and Celia's wedding, this thus the first time he will have met his daughter-in-law. Unknown to John Sr. who has always treated Johnny as the favored son, both Johnny and Polo have a strained relationship with him in he never being there when they need him. What John Sr. did not tell them before the arrival of his two day stay is that he has come specifically for $2,500 Polo had promised was his whenever he needed it, he wanting it for his retirement plans, with the problem being that Polo no longer has the money which further places Polo in John Sr.'s bad books. All of these issues stem directly from a secret Johnny is keeping, with Polo the only one in the family who knows: that Johnny is a two fix a day junkie, he having become addicted to morphine when he was in the hospital at the end of his military service. Polo's saved $2,500 went to Johnny for his fixes, while Johnny immediately owes "Mother", his primary supplier, $500 - money which Johnny doesn't have - Mother who knows the fine line of getting the money versus keeping Johnny hooked and thus keeping him as a lucrative customer.—Huggo
In a housing project apartment in Lower East Side New York City, Johnny Pope (Don Murray) lives with his pregnant wife Celia (Eva Marie Saint) and his younger brother Polo (Anthony Franciosa). Johnny is a veteran who recently returned from the Korean War, in which he sustained an injury while surviving for days trapped in a cave. His survival made him a hero in the newspapers, but his ensuing recuperation in a military hospital left him secretly addicted to the painkiller morphine, with Polo his only family member aware of his condition.
Johnny and Polo's father John Sr. (Lloyd Nolan) arrives in New York from his home in Florida to visit his sons and collect $2,500 that Polo had saved and promised to him whenever he wanted it. John Sr. has just fulfilled his dream of quitting his job and buying his own bar and needs the money to pay for repairs and remodeling. Polo tells his father that he spent the money but refuses to say what he purchased. John Sr. becomes angry and refuses to speak to Polo, continuing his usual pattern of praising Johnny and belittling Polo.
John Sr. expresses his pride in Johnny's war service and that he has married a fine wife, is starting a family and lives in a nice apartment, while Polo is renting a room from his brother, is unmarried and works in a bar that his father considers low-class. John Sr. and Celia do not know that Polo gave the money to Johnny, who spent it all on his $40-a-day drug habit. John Sr. is also unaware that Johnny has lost four jobs in a row because of his habit and that Johnny and Celia are on the verge of divorce because Johnny ignores her and often leaves for hours, sometimes for a full night. Celia thinks that he is seeing another woman, but he is actually seeking drugs, which are becoming harder to find as the police are arresting many dealers.
While John Sr. is visiting, Johnny's dealer "Mother" (Henry Silva) comes to the Popes' apartment with his henchmen Apples (William Hickey) and Chuch (Gerald S. O'Loughlin), ready to beat Johnny badly because he owes Mother $500 and has no money to pay. Johnny begs for enough dope to last him until his father returns to Florida the next day, and Mother gives him one dose but warns him that he needs to pay at least $300 by the next day or they will put him in the hospital. Mother gives Johnny a gun and suggests that he commit robbery to acquire the money.
After arguing with Celia, Johnny leaves and spends the night walking the streets. He tries to rob several people at gunpoint but is unable to commit the crime. At the apartment, a drunk Polo confesses his love for Celia, who in her loneliness and desperation is almost ready to return his love. Despite their mutual feelings, they fall asleep in separate rooms.
When Johnny returns in the morning, he is feeling withdrawal symptoms and needs to meet a dealer for a fix, but his father expects to spend the day with him. Johnny tries to convince his father to spend the day with Polo instead. but John Sr. does not want to talk to Polo, causing an emotional confrontation. John Sr. finally agrees to attend the football game with Polo.
Johnny coerces Polo into driving him to meet the dealer by threatening to throw himself out of the car in traffic, but when Johnny arrives at the meeting place, the dealer is being arrested. Johnny goes into severe withdrawal and begins to hallucinate just as Mother and his gang arrive to collect Johnny's payment. Upon learning that Johnny does not have the money, they give him one dose in exchange for the $12 that Polo has in his wallet and tell Polo to sell his car to cover Johnny's $500 debt. Polo pleads with Johnny to tell Celia that he is a junkie.
The fix temporarily cures Johnny's withdrawal, and he tries to reconcile with Celia by preparing a romantic dinner. However, she tells Johnny that she no longer loves him and wants a divorce. When he confesses that he is a junkie and that his habit has caused his absence and inattention, she reacts supportively. John Sr. and Polo arrive for dinner and Johnny informs his father that he is a junkie and that Polo's $2,500 was spent on drugs for him. His father becomes angry, causing Johnny, who is going into withdrawal again, to flee the apartment. Celia then becomes ill and is rushed to the hospital to avoid losing the baby. When Johnny returns, he is menaced by Mother but is saved by Polo, who pays Mother $500 that he obtained by selling his car.
Johnny announces his intention to overcome his habit, even throwing a package of dope back to Mother. John Sr. and Celia return, and Celia takes charge, reassures Johnny and calls the police to bring Johnny to the hospital.
