Once an assistant to the great Japanese master Yasujiro Ozu (Tokyo Story), director Shohei Imamura (The Ballad Of Narayama, Vengeance Is Mine) has spent much of his remarkable career in rebellion, answering Ozu's austere classicism with bold, pitch-black examinations of the country's seedier elements. But in his old age, Imamura has drifted steadily back toward his mentor with deft, lyrical comedies such as 1997's The Eel and 1998's Dr. Akagi, which don't abandon his taboo themes so much as underscore them with surprising sweetness and optimism about human nature. His new film, the funny and endearing sex comedy Warm Water Under A Red Bridge, fits squarely within this impressive late-period stretch, even as it shows that his taste for outrageous perversity and ribald humor hasn't abandoned him. The clever, double-meaning title refers to the special case of Misa Shimizu, an attractive and demure single woman with a strange erotic quirk: Whenever she reaches orgasm, she literally erupts like an open hydrant, spraying torrents of water all over the walls, windows, ceiling, and floor. Her desire for release lures an unwitting partner in Koji Yakusho, an unemployed white-collar businessman from Tokyo who travels to her quaint seaside village seeking a valuable Buddha hidden somewhere in her house. With his estranged wife and son another world away, Yakusho settles into the simple life of a fisherman and happily accommodates Shimizu's insatiable sexual appetite. But when the well starts to run dry and real feelings trickle into the relationship, he's gripped by restlessness and strong pangs of jealousy, worried that she's getting her considerable needs met by someone else. As in his last few features, Imamura populates the small-town backdrop with a gallery of colorful characters, including three old fishermen who benefit from the nutrients Shimizu floods into the water supply and an African marathon runner who figures into the film's most inspired visual gag. A minor work by any measure, Warm Water Under A Red Bridge thins out its irresistible conceit by the second hour, just as the novelty wears off for Yakusho himself. But even at its most lackadaisical, Imamura's obvious affection for his characters and the idyllic community makes the time pass pleasantly, with enough offhand amusements to carry his slice-of-life to a transcendent conclusion. Now two films past his supposed "retirement," the once-pessimistic Imamura seems unusually playful and high-spirited, and the mood suits him well.