In 1968, Michael arrives at his apartment on the Upper East Side of Manhattan in preparation for Harold’s birthday party. Michael receives a call from his boyfriend Donald, who will be arriving early due to a canceled psychiatrist appointment. When Donald arrives, Michael pities his own aging and debt-riddled lifestyle. Alan, Michael’s old roommate from Georgetown, calls Michael in tears saying he has something urgent to tell Michael in person. Michael invites Alan to the party and warns all his guests that Alan is heterosexual and doesn’t know about Michael’s homosexuality.
As the sun sets, Emory arrives with lovers Hank and Larry, whose relationship is on the rocks. Bernard arrives with a stack of books for Donald before he too settles into the party atmosphere. Alan calls Michael from a phone booth, informing him that he isn’t coming to the party after all and will instead meet Michael the following day for lunch. Larry and Bernard dance to “Heat Wave” as Emory and Michael join in. Despite his earlier conversation with Michael, Alan arrives at the party and finds Michael and his friends dancing. He bonds with Hank, who he mistakes as being straight, and shows discomfort towards Emory’s flamboyant behavior. Michael takes Alan to his bedroom to discuss Alan’s urgent conversation, but Alan dodges his questions.
Cowboy arrives earlier than Emory expected and mistakes Michael for Harold, kissing him on the lips. Alan descends from the upstairs bathroom and announces he’s leaving. Emory chides him for being a closeted homosexual which results in Alan punching Emory and calling him a “faggot.” Harold arrives high on marijuana and accepts Cowboy’s gift of a passionate kiss. Michael begins to drink and smoke despite having quit 5 weeks prior. He and Harold trade vicious insults as Hank helps a vomiting Alan in Michael’s bathroom. Emory brings out Harold’s birthday cake and presents. After opening them on the terrace, a thunderstorm forces everyone inside.
Alan tries to leave again but is stopped by Michael, who informs everyone that they are playing a party game: everyone must use the telephone to call the one person they truly believe they have loved. Michael creates a points system based on how far each one can get in their conversations with their true loves. Bernard calls the son of his mother’s employer, with whom he had a sexual encounter as a teenager. After his call goes awry, he only earns 2 points. Emory solemnly calls a dentist he had a crush on in high school but his call ends abruptly, earning him 3 points. Hank calls his answering service at home and leaves a message for Larry, earning him 7 points. Larry loudly disagrees with Hank about the insistence of monogamy in their relationship, leading Michael to deduce that Donald and Larry have had sex in the past. Larry uses the kitchen phone to call Hank in the living room. His tearful declaration of love earns him 10 points. Hank and Larry go upstairs to Michael’s room.
Michael angrily confronts Alan about his closeted relationship in college with a boy named Justin. Alan makes a phone call to who Michael believes is Justin, but turns out to be Alan’s wife Fran. Alan tells her he loves her and is coming home to Washington. He earns 10 points and leaves as Michael stands defeated. Harold informs Michael that no matter what Michael does, he will always be a homosexual, just like the rest of them. He departs, taking Cowboy and his presents with him. Emory leaves with a distraught Bernard, promising to sober him up on the way home. Michael laments over the group’s treatment of each other, wishing “if we could just not hate ourselves so much.” He tells Donald that he never learned what Alan wanted to confide in him.
As midnight nears, Michael attends Mass at St. Malachy’s. Donald reads The Golden Notebook on Michael’s couch, despite his earlier insistence he would not be spending the night. Harold and Cowboy ride in a taxi to Harold’s home, Emory and Bernard sit at a late night diner enjoying coffee and buttered toast, Hank and Larry have sex in Michael’s bedroom, and Alan sits at a bar drinking alone. Michael exits Mass; his walk turns into a run as he heads down the street.