New Orleans, 1937. The story revolves around Catherine Holly, portrayed by Elizabeth Taylor, a young woman who finds herself in a mental institution following a significant emotional breakdown triggered by the mysterious death of her cousin, Sebastian Venable. This tragic event unfolded during a holiday they shared in Spain just a few months prior. His wealthy mother, Violet Venable, played by Katharine Hepburn, is desperate to suppress the truth surrounding Sebastian's untimely demise. In a drastic attempt to silence Catherine and ensure no secrets emerge, she offers a substantial bribe to hospital administrator Dr. Hockstader (Albert Dekker), proposing to fund a new wing for the institution if he can persuade brilliant young surgeon Dr. John Cukrowicz (Montgomery Clift) to perform a lobotomy on Catherine.
In a crucial meeting at her estate’s lush garden, which she describes as "like the dawn of creation," Mrs. Venable discusses her niece's case with Dr. Cukrowicz. During this conversation, she characterizes Sebastian as a poet who was more preoccupied with his art than with life, highlighting his yearly habit of writing a single poem each summer. She fondly reminisces about their shared vacations and reveals a haunting poem about witnessing the grotesque sight of birds devouring hatchling turtles—an event where Sebastian purportedly glimpsed "the face of God."
Eventually, Dr. Cukrowicz decides to evaluate Catherine, who has been isolated in a private women’s mental institution since returning from Europe. Initially, he observes her from a distance, noting an incident where she defiantly extinguishes a cigarette on her own palm in front of Sister Felicity (Joan Young). This alarming act is perceived by the nun as evidence of Catherine's instability. In their subsequent discussion, she expresses a fragmented memory, admitting that the last moment she recalls occurred before her trip to Europe—a traumatic event she refers to as the day she "lost her honor."
As the plot unfolds, Catherine's family shows up, revealing that Sebastian has left a significant inheritance in his will. However, Mrs. Venable withholds access to the funds unless they agree to commit Catherine and permit the lobotomy. In a desperate bid for freedom, Catherine attempts to escape, finding herself in a nightmarish scenario on a catwalk above the male patients, leading to a harrowing encounter.
Their strained exchanges escalate, especially when Catherine challenges Mrs. Venable about her true connection to Sebastian, hinting at sordid secrets and complicity. Mrs. Venable’s fainting spell allows Catherine to momentarily disengage from the confines of the institution. Yet, she faces further struggles, including an intense moment of vulnerability as she contemplates jumping from the catwalk but is thwarted by an orderly.
Determined to unlock the truth, Dr. Cukrowicz takes Catherine back to the Venable estate, employing truth serum in a tense confrontation attended by her family and hospital staff. In a gripping recollection, Catherine navigates through memories of their sun-soaked days in Cabeza de Lobo, where she learns the disturbing reality that Sebastian used her as bait to lure local boys. The shocking conclusion reveals her gruesome witness to Sebastian’s death, as he falls victim to a mob of starving children who consume him.
As the shocking truths unfold, Catherine collapses in despair while Mrs. Venable’s delusions become increasingly evident, revealing her denial of her son's sexuality and a desperate grip on reality. The film culminates as Mrs. Venable, now profoundly unhinged, mistakes Dr. Cukrowicz for Sebastian, leading to a chilling revelation as Catherine begins to recover, equipped with the harrowing truths she has uncovered. Together, they retreat into the house, seeking solace in the aftershocks of a traumatic but liberating revelation.
