With the possible exception of Kurosawa, Nagisa Oshima (In the Realm of the Senses, Empire of Passion, Merry Christmas, Mr. Lawrence) is the greatest living Japanese filmmaker. Unfortunately, the U.S. distributor of most of his early work has made very little of it available on video, which means that most Americans' knowledge of the modernist Japanese cinema doesn't include Death by Hanging, Boy, The Man Who Left His Will on Film, The Ceremony, and many other Oshima masterworks. Max Mon Amour (1986), his most recent feature, here receiving its belated Chicago premiere, isn't as good as those movies, but then what is? This dry drawing-room comedy about an English diplomat's wife (Charlotte Rampling) who has a "serious" affair with a chimpanzee was produced by Serge Silberman, producer of Bunuel's last films, and written by Bunuel's cowriter on the same films, Jean-Claude Carriere. Much of this film's ongoing humor derives from the human couple's sense of decorum; in a game effort to preserve his marriage, the diplomat (Anthony Higgins), who has a mistress of his own, arranges to have the chimp moved into their flat. Even for a filmmaker who essentially changes style with each picture--and has a reputation as a taboo breaker--this is uncharacteristic: the poker-faced surrealism of "civilized" people attempting to be mature about a woman's passion for a chimp seems, not surprisingly, more like Bunuel than Oshima. Facets Multimedia Center, 1517 W. Fullerton, Friday and Saturday, April 8 and 9, 7:00 and 9:00; Sunday, April 10, 5:30 and 7:30; and Monday through Thursday, April 11 through 14, 7:00 and 9:00; 281-4114.