The Civil War is ending. Seth Beckwith, Henry Hull, an old family servant, awaits the return of various members of the Mannon family—especially Ezra Mannon, Raymond Massey, the patriarch and a general in the Union Army. Seth shows neighbors around the house, and the women recall a 20-year-old scandal: Ezra's brother, David Mannon, had to marry the French nurse who worked for their father, Abe. Abe banished the couple, destroyed the family home and built a new one “out of pure hate.”
In New York City, Lavinia Mannon, Rosalind Russell, follows her mother Christine Mannon, Katina Paxinou, to the residence of sea captain Adam Brant, Leo Genn, and is shocked to see them kiss. She remembers sharing a passionate kiss with Brant.
Christine returns home. Lavinia, preoccupied with the memory, refuses to see Peter Niles, Kirk Douglas, who has just proposed to her. Niles’ sister Hazel Niles, Nancy Coleman, seeks news of Lavinia’s brother Orin.
Seth tells Lavinia that Adam is actually David’s son, encouraging her to challenge the man. When she does, Adam pours out the true story of how their grandfather coveted the girl and revenged himself on David. But Adam’s greatest hate is for Ezra, who did not reply to his mother’s plea for a loan when she was starving. Adam swore revenge.
Lavinia confronts her mother, who declares that she has hated Ezra since their wedding night. The “disgust” she felt poisoned her relationship with Lavinia from the day she was born. Lavinia, who worships her father, blames Christine. Christine knows who Adam is and loves him. She knows Lavinia loves Adam. But Lavinia forces her to give him up by threatening to tell Ezra the truth. She paints a grim future if they run away—and the difference in their ages grows more plain.
Ezra has a weak heart, and Christine tells Adam what poison to purchase in Boston. As he walks away, she whispers to herself that he will never be able to leave her now.
Ezra returns home. His harrowing experiences during the war have changed him. He has loved Christine always and begs her to help “smash the wall” between them. Christine tells him she loves him, and Lavinia interrupts their kiss. But in their bedroom, the mutual hate pours out of both of them, and Ezra has a heart attack. Christine gives him medicine. He dies in Lavinia’s arms, pointing at his wife and saying “Not medicine”.
> Not medicine
When Christine faints, Lavinia takes the box of pills.
Orin comes home, his head wound bandaged. He and his mother talk about their special relationship. (He only courted Hazel to make her jealous.) But Christine’s obsession with putting Lavinia in the wrong backfires, and Orin believes Lavinia when he sees his mother’s reaction to the pillbox.
On board Adam’s ship, Orin and Lavinia witness Christine and Adam planning to flee. Orin shoots Adam in the back. “How could you love that vile old woman so?” Lavinia asks the corpse. They make it look like robbery and boast of it to Christine, who commits suicide with Ezra’s pistol. Orin is shattered.
Some time later, Orin and Lavinia return home from the islands. Lavinia is the image of her mother, dressed in white and wearing the same elaborate coiffure. Peter returns, and Orin, bearded as his father was, has been driven mad by guilt. He gives Hazel a document to open if he dies or if Lavinia tries to marry Peter. Panic-stricken, Lavinia promises anything if he takes it back. He does. Peter returns, and Orin takes the opportunity to kill himself.
Lavinia, dressed in mourning, waits for Peter. Hazel accuses her of driving Orin to suicide. She begs Lavinia to let Peter read what was in the envelope. Lavinia burns it. Peter arrives. He has quarreled with his family but still wants her. In Lavinia’s frenzied embrace she calls him “Adam.” She sends him away to reconcile with his family, confessing falsely to an affair with a native islander. To the sound of Seth closing the shutters on all windows, she withdraws into the house, there to be punished by the Mannon dead.
