Though author Herman Raucher admits to moving the order of certain events around and interchanging some dialogue, the movie is (according to those involved) an accurate depiction of events in Raucher's life in the summer of 1942 on Nantucket Island; he didn't even change anyone's name. He began writing the screenplay as a tribute to his friend Oscy, who'd been killed in the Korean War, but midway through writing it Raucher realized that he wanted to make it a story about Dorothy, who he had in fact neither seen nor heard from since their last night together as depicted in the movie. Raucher admits that in all the time he knew her, he never bothered to ask her what her last name was.
During an interview on "The Mike Douglas Show" (1961), Herman Raucher said that after the novel and movie were released, several women wrote letters to him claiming to be Dorothy. One of the letters was indeed from the real Dorothy, who wanted to know if she had psychologically damaged Raucher, and also informed him that had been happily remarried and was now a grandmother. It was the last time that Raucher, by that time married with children, heard from Dorothy.
The telegram on Dorothy's coffee table at the end of the movie lists her and Pete's last name as Walker.
Though unspoken in the film, the novel and script provide several characters' names and/or full names: Hermie is Herman Raucher, Oscy is Oscar Seltzer, and Dorothy's husband is named Pete.