Rachel Weisz in Terence Davies's Film "The Deep Blue Sea" THERE is a fine line between mad love and pure madness. In "The Deep Blue Sea" Hester, the beautiful wife of a judge, falls hopelessly for a younger ex-fighter pilot who forgets her birthday, a slight that plunges her into suicidal despair. The film begins as she awakens from an unsuccessful act of desperation, and unfolds mostly over the course of a single day, exploring Hester's unraveling through flashbacks. A meditation on the ravages of erotic love set in repressive postwar Britain, the film is adapted from a 1952 play by Terence Rattigan, though it bears the unmistakable stamp of its director, Terence Davies, a noted chronicler of that era in films like the semi-autobiographical "Distant Voices, Still Lives" (1988). But Mr. Davies said by phone from his home in Mistley, England, that for him the emotional landscape of this story was uncharted. "Erotic passion can happen to anyone," he said. It hasn't happened to me. Never? "Never," confirmed Mr. Davies, 66, a gay man who said he had been celibate for 30 years. He laughed after it was suggested that perhaps he had been lucky to have been spared. "I'm afraid of the world, I always have been," he continued. I'm afraid of other people. My nature is basically of an outsider looking in. But I have some passions in my life. I couldn't live without the "Four Quartets," without the sonnets. I think I can empathize even if I haven't gone through it myself. I think I can speak with another's voice. Sean O'Connor, a producer of the film, wrote in an e-mail that Mr. Davies, whose previous fiction film was "The House of Mirth" in 2000, was the "first and only" director he had in mind to remake "The Deep Blue Sea," which originally found its way onto the screen in a 1955 production directed by Anatole Litvak starring Vivien Leigh. Mr. Davies's version opens in New York on March 23; his work is also the subject of a retrospective at BAMcinématek this month. "Terence is 66 years old and has never had a "proper" relationship, so is very uncertain on issues of sex and sexuality," Mr. O'Connor wrote. In actuality - whether he's aware of it or not - sexual repression is one of his major themes. That's why he is so at ease in examining England in the 1950s. In adapting the play Mr. Davies radically cut exposition and shifted the point of view entirely to Hester. He was inspired by the women's pictures of the "40s and "50s that he grew up watching with his sisters, films that revolved around stars like Joan Crawford and Bette Davis. Mr. Davies pointed out that in 1950s Britain women like Hester (played by Rachel Weisz) did not leave their husbands. "What people didn't like, and it's still true in this country, they don't like passion," Mr. Davies said. They find it vulgar. Hester is a very conventional woman, but she does something that is very unconventional for the time. That takes a lot of courage. What made the play daring for its time was having as its heroine a middle-aged woman who renounces her vows and social standing to follow her heart to a dingy flat with her working-class lover. She unapologetically sacrifices everything for a man whose infatuation never blossoms into love, and she nearly self-destructs in the process. But Ms. Weisz said by phone from London that she was attracted to the role because of its timeless themes. "It didn't feel dated," she said of Mr. Davies's script. It's a very moving existential story about a human being's bid for freedom, and I don't think that ever goes out of fashion. "The story really made sense to me," Ms. Weisz added. She's in a safe, comfortable place with her husband, and they have intellectual repartee, and he's very sweet and kind and a decent man, but she's fallen in love. She makes a complete and total fool of herself, and she can't control it. And there's something really fascinating about that. Some have read into the story a veiled exploration of gay themes of sexual awakening, forbidden love and the dangers of defying convention. The play is rumored to have been inspired by an incident in Rattigan's life, when an ex-lover killed himself over another man. "The theme is absolutely there in the play and in the film - particularly with regards to Rachel's performance," said Mr. O'Connor, the producer. She's playing a woman who is repressed by her gender, class and background and runs off with a sexy young man - giving up her entire life to do so. It's not hard to see the symbolism for a gay writer like Rattigan writing at that time. But Mr. Davies said he didn't see it. "The film is about the nature of love," he said. These three people love each other but in different ways that can't be returned, and that's sad. But that's what makes the triangle so interesting. Hester's husband (played by Simon Russell Beale) is crestfallen that the companionship and lifestyle he offers is not enough. Hester is overcome by love for a man, Freddie (Tom Hiddleston), who can't comprehend how she can throw away her life over a romantic disappointment, having witnessed the senseless sacrifice of life during wartime. "What Freddie doesn't understand is she's found real sex at 40," Mr. Davies said. It overwhelms her. But he can't see that, and she can't understand why he doesn't see it. Of course that's the nature of human relationships, isn't it? Mr. Davies has become one of Britain's most respected auteurs despite having made just seven films in the last few decades. He will be in New York for BAMcinématek's March 15 sneak preview screening of "The Deep Blue Sea," and said he was always apprehensive about traveling, anxious as he is about getting lost: "Even in America, where we have a common language and most of the cities are on the grid system, it's a constant worry." But what about getting lost in another person, the way that Hester does with Freddie? Was making the film an exercise in imagining what that metaphorical journey might be like? "I'm a very conventional man, and I just wish I were a little more adventuresome and not so dull and prepared to take risks, but I'm not," Mr. Davies said. People say, well you've taken risks in the work. But I say, I've made them as I've seen them and heard them. That just seems to be true to your inner voice, and I don't see that as a risk at all.