Late one night, a drunken Brick Pollitt (Paul Newman) is out trying to recapture his glory days of high school sports by leaping hurdles on a track field, dreaming about his moments as a youthful athlete. Unexpectedly, he falls and breaks his leg, leaving him dependent on a crutch. Brick, along with his wife, Maggie “the Cat” (Elizabeth Taylor), are seen the next day visiting his family’s estate in eastern Mississippi, there to celebrate Big Daddy’s (Burl Ives) 65th birthday.
Depressed, Brick has spent the last few years drinking, while resisting the affections of his wife, who taunts him about the inheritance of Big Daddy’s wealth. This has resulted in an obviously tempestuous marriage—there are speculations as to why Maggie does not yet have a child while Brick’s brother Gooper (Jack Carson) and his wife Mae (Madeleine Sherwood) have a whole pack of children.
Big Daddy and Big Mama (Judith Anderson) arrive home from the hospital via their private airplane and are greeted by Gooper and his wife—and all their kids—along with Maggie. Despite the efforts of Mae, Gooper and their kids to draw his attention to them, Big Daddy has eyes only for Maggie. The news is that Big Daddy is not dying from cancer. However, the doctor later meets privately with first Gooper and then Brick where he divulges that it is a deception. Big Daddy has inoperable cancer and will likely be dead within a year, and the truth is being kept from him. Brick later confides in Maggie with the truth about Big Daddy’s health, and she is heartbroken. Maggie wants Brick to take an interest in his father—for both selfish and unselfish reasons, but Brick stubbornly refuses.
As the party winds down for the night, Big Daddy meets with Brick in his room and reveals that he is fed up with his alcoholic son’s behavior, demanding to know why he is so stubborn. At one point Maggie joins them and reveals what happened a few years ago on the night Brick’s best friend and football teammate Skipper committed suicide. Maggie was jealous of Skipper because he had more of Brick’s time, and says that Skip was lost without Brick at his side. She decided to ruin their relationship “by any means necessary”, intending to seduce Skipper and put the lie to his loyalty to her husband. However, Maggie ran away without completing the plan. Brick had blamed Maggie for Skipper’s death, but actually blames himself for not helping Skipper when he repeatedly phoned Brick in a hysterical state.
After an argument, Brick lets it slip that Big Daddy will die from cancer and that this birthday will be his last. Shaken, Big Daddy retreats to the basement. Meanwhile, Gooper, who is a lawyer, and his wife argue with Big Mama about the family’s cotton business and Big Daddy’s will. Brick descends into the basement, a labyrinth of antiques and family possessions hidden away. He and Big Daddy confront each other before a large cut-out of Brick in his glory days as an athlete, and ultimately reach a reconciliation of sorts.
The rest of the family begins to crumble under pressure, with Big Mama stepping up as a strong figure. Maggie says that she’d like to give Big Daddy her birthday present: the announcement of her being pregnant. After the jealous Mae calls Maggie a liar, Big Daddy and Brick defend her, even though Brick knows the statement is untrue and Big Daddy thinks the statement may be untrue. Even Gooper finds himself admitting, “That girl’s got life in her, alright.” Maggie and Brick reconcile, and the two kiss, with the implication that they will possibly make Maggie’s “lie” become “truth”.