Irene Redfield, a light-skinned black woman residing in Harlem, unexpectedly encounters her childhood friend, Clare, at a hotel. While Irene embraces her identity as African-American and is married to a black doctor, Clare has chosen to "pass" as white and is married to a wealthy white man, John. Inviting Irene to her hotel, Clare shares that after her father passed away, she was brought up by two white aunts and wed at an early age. Their reunion is interrupted by John, who shows a blatant disdain for African-Americans, completely oblivious to his wife’s real heritage and Irene's circumstances of "passing" for the day.
Despite this shaky first meeting, Clare rekindles the friendship by reaching out to Irene, who, after some contemplation, agrees to reconnect. As they dive deeper into each other's lives, insecurities surface, and Clare confesses her longing for the African-American culture she has had to suppress around John. Irene introduces Clare to a jazz club outing with her husband, Brian, and their friend Hugh. Although Hugh dismisses the bash, Irene can't overlook the undeniable chemistry brewing between Clare and Brian.
As they reminisce, Clare expresses her envy of Irene's steady, moral nature, while Irene admits to admiring Clare's lively and liberated spirit. Clare reveals her willingness to achieve her desires by any means necessary, even at the expense of others. Meanwhile, Irene and Brian find themselves clashing over how to address racial issues with their children. Irene grows increasingly concerned as Brian and Clare seem to cultivate a close bond, leaving her sons eager to see Clare.
After spending a day home with the children while Brian enjoys bridge with Clare, Irene's growing paranoia leads her to suspect an affair between them, resulting in a tense confrontation with Brian. Attempting to distance herself from Clare, Irene's plans are thwarted when Brian invites Clare to a tea gathering for Hugh. In an attempt to mask her anxiety, Irene drinks heavily and accidentally breaks an heirloom teapot upon witnessing Brian and Clare in an intimate moment, although Hugh quickly shields her from the guests' scrutiny.
Despite Irene's desire for Clare to return to John and leave the city, Clare remains present in Irene's life. While shopping with Felise, who does not pass as white, Irene runs into John and hurries away as he begins to suspect his wife’s true identity. Although Irene desperately tries to warn Clare, she ultimately relents. As the trio prepares for a party, Irene questions Clare on her plans if John discovers her background. Clare's response—a commitment to return permanently to Harlem—disturbs Irene, rendering her silent throughout the event.
When she opens a window to smoke, an irate John storms into the party, confronting Clare and accusing her of deception. As John lunges at Clare, Irene instinctively intervenes, but in the ensuing chaos, Clare tragically falls from the window to her demise. After a moment's hesitation, Irene descends to where the guests are conferring with the police. When questioned, she maintains that Clare's fall was an accident. In the midst of her sorrow, Brian appears to comprehend the underlying truths of the situation and consoles Irene as she weeps.
