With the coming of summer, three high school buddies--Kenny Leeds, Mike Decker, and Tommy Kingsley--anticipate their initiation into the pleasures of manhood. But Kenny is separated from his friends and sent to stay with his grandparents in Buffalo while his father, a widowed salesman, leaves on a business trip with his secretary-fiancée. Bored and alone in a strange city, Kenny writes his two friends letters about his adventures at "Rosie's," a fictitious brothel across the Canadian border in Niagara Falls. His lie quickly backfires, however, when Mike and Tommy, en route to summer camp, arrive in Buffalo eager for a visit to "Rosie's." While stalling for time, Kenny takes them on an aimless tour of Niagara Falls and points to a boarded-up building and pretends that the brothel must have been raided by the police. Certain there must be other such places, the boys stop at a discotheque and meet Anna, an English girl whom they mistake for a prostitute. She tells them she has lost her passport and needs help in crossing the border, so the boys smuggle her into Buffalo and bring her back to Mike and Tommy's hotel. As she sleeps in their room, they draw lots to determine who will make love to her first. Mike and Tommy precede Kenny, but both are too timid to go through with their intentions, and they decide to conceal their failure from Kenny. Before Kenny enters the room, he hears Anna talking on the telephone and learns that her married lover had decided to end their affair. Although she is at first resentful of Kenny's presence, Anna responds to the boy's awkward confusion, not unlike her own, and accepts him lovingly. The next morning, Kenny escorts Anna back to the Canadian border and discovers that she is not a call girl and that she did not make love with Mike and Tommy. Kenny asks her why she behaved differently with him, but she responds only with a smile and farewell kiss.