Aficionados of cerebral puzzle movies–I’m not talking here about your conventional whodunits, but real brain-teasers like “The Last of Sheila” (1973), with its extravagantly complicated script by Stephen Sondheim and Anthony Perkins, or the Coens’ wonderfully serpentine “Blood Simple” (1983), or Bryan Singer’s “The Usual Suspects” (1995), with its elaborate game of misdirection concocted by Christopher McQuarrie–should be in heaven watching Christopher Nolan’s stylishly labyrinthine “Memento.” The picture is at once a gorgeously-wrought homage to the delectable old film noirs based on works by writers like Fredric Brown and Cornell Woolrich, and a sophisticated reworking of the convoluted structural tricks that Quentin Tarantino played in “Pulp Fiction.” Fans of crude spring-break laughfests and explosive-laden actioners will undoubtedly find the film mystifying and frustrating (you’re advised to seek out a quiet, empty theatre where viewers around you won’t be gabbling “What’s going on?” endlessly to one another), but anybody with a taste for the bizarre and the challenging will embrace it.

The narrative involves Leonard Shelby (Guy Pearce), a tormented fellow who’s bent on discovering who murdered his wife; the twist is that in that assault that led to her death, Leonard was injured, leaving him with amnesia. Now I know what you’re thinking–the lost, troubled amnesiac perpetually in danger and only haltingly discovering the truth about himself has been a staple of pulp novels, B-movies and long-forgotten TV from time immemorial: one need only think of Roy William Neil’s underrated “Black Angel” (1946), based on a novel that Woolrich published under the name of William Irish, in which Dan Duryea, in a complete haze as a result of his alcoholism, is similarly driven to find his wife’s killer; or Wolfgang Petersen’s “Shattered” (1991), featuring Tom Berenger as an accident victim desperately searching for the truth about himself; or the short-lived CBS series “Coronet Blue” (1967), which featured Frank Converse as an amnesiac survivor of an assassination attempt looking for his own identity and the truth about his past while trying to avoid his would-be killers. The twist here is that the protagonist is suffering not from the usual run-of-the-mill amnesia, but from short-term memory loss–an affliction which allows him to recall everything that occurred up until his wife’s death, but nothing that’s happened afterwards for more than a few seconds; as a result his comprehension of reality is always fragmentary and distorted (as is ours along with him), and he has to rely on Polaroid photos and scribbled notes to inform him of where he’s living, what car he drives, and anything he’s previously learned in his search (whether right or wrong). (There’s one beautiful moment when he doesn’t even recall whether he’s chasing somebody or being pursued.) To make things even more complicated, Nolan tells the story backwards, thereby keeping us (as well as Shelby) constantly disoriented; and he repeats material and alters perspective to give the whole picture the air of a half-remembered, vaguely menacing nightmare. He also periodically intercuts Shelby’s recollections about a man (Stephen Tobolowsky) who suffered from the same condition he now endures (Shelby had investigated the case, we’re told, in his previous life as an insurance adjuster).

The result is a narrative that forces you to work hard to keep up with it and sort out the clues that point to the outcome of the hero’s search. A viewer must come to the picture alert and clear-headed in order to meet the challenge. And any brief distraction–a trip to the concession stand or the facilities, even a whispered comment that requires you to turn your eyes from the screen–can be disastrous. You have to be willing to shut up, watch intently, and think about the information you’re being given in scattered, sometimes misleading shards. f you can’t do that, “Memento” isn’t for you: it won’t appeal at all to the lazy or inattentive. But if you’re ready to go with it, you’ll be pleased to know that it plays fair. The denouement isn’t quite up to one’s hopes, as if often the case in such puzzle pictures; but in these cases, the journey is usually more satisfying than the destination.

“Memento” can be criticized for being entirely synthetic and artificial; its structure allows Nolan to take any tangent he chooses in shaping Shelby’s past, and the directions in which the plot goes are in fact quite arbitrary. It’s also well-nigh impossible to work up much emotional investment in Leonard, despite the fact that Pearce plays him with conviction and vigor (and a remarkably good American accent); he’s just the standard tormented pulp protagonist. The only other performers of much consequence are Joe Pantoliano, properly seedy as an acquaintance who keeps popping up in Leonard’s life and may be friend or foe, and Carrie-Anne Moss, nicely restrained as a bartender-waitress who’s either helping Shelby or using him for her own purposes–and they’re merely playing types that come right out of pulp fiction (the genre, not the flick) too, so it’s difficult to care about them, either. But if the picture lacks depth, it remains a fascinating curiosity, with a surface sufficiently intriguing to compensate; sharply written, ingeniously constructed, strikingly shot and fast-paced, “Memento” is at once a satisfying mental game and an exhilarating cinematic stunt.

Bigamy has been the subject of film comedies in the past–remember “The Remarkable Mr. Pennypacker” (1958), starring sharp-tongued Clifton Webb as a guy with two families, or “The Captain’s Paradise” (1953), with Alec Guinness as a steamer captain with a wife in each of two ports, or “The Bigamist” (1956), with Marcello Mastroianni as a young fellow wrongly accused of the crime? We’ve even had guys with more than two wives treated as a joke–Rex Harrison had five in “The Constant Husband” (1955), though as an amnesiac he didn’t remember them all. In “Me You Them” Elena Soarez and Andrucha Waddington tell the story, loosely based on a real incident, of a woman named Darlene (Regina Case) in an impoverished region of northeastern Brazil who, over the course of the years, acquires three “husbands,” along with a child by each one (she’d previously had a child by a fourth man, with whom she eventually leaves him)–all living together, in a small farmhouse and in relative amity by picture’s end.

It’s difficult to know what to make of the film. Certainly it’s beautifully photographed, capturing the parched but nonetheless impressive vistas of the rural countryside in spectacular wide-screen cinematography. But the emotional tenor of the piece is peculiar, to say the least. The distributor refers to it as a “bittersweet comedy,” but it’s certainly not very funny; there’s a droll matter-of-factness to the curious arrangement that develops among the characters, perhaps, but as a whole the film never becomes charming enough to elicit more than an occasional smile. Nor is it especially dramatic; while it captures the bleakness of life in the region nicely in purely pictorial terms, it nevertheless presents its characters as largely easygoing if sometimes a bit hard-pressed, and its lackadaisical, oddly somnolent tone doesn’t engage the viewer at all. The picture just meanders from incident to incident, with births and funerals sprinkled in from time to time, ending up as a rather desultory affair. Presumably we’re supposed to be struck by what each of the three “husbands” brings to the arrangement–the oldest, the dyspeptically tyrannical Osias (Lima Duarte) representing security, the second (his cousin Zezinho, played by Stenio Garcia) a naive sweetness, and the third (the young drifter Ciro, played by Luiz Carlos Vasconcelos–sexual power; but whether this is merely an elaborate fable designed to argue that a true man should possess all three qualities is never made clear. As for Darlene herself, the joke seems to lie in the fact that she’s basically a homely woman who nonetheless proves irresistible to all sorts of guys and, though occasionally railed at by them, can inevitably twist them to her desires; but as Case plays her she seems more torpid than seductive. This is one surprisingly lethargic Earth Mother.

There may be some in the viewing audience who will perceive “Me You Them” as a kind of vaguely feminist tale and embrace it on that basis. But despite its often striking images, the picture never manages to rise above the tedious and humdrum. (Of course, it means to depict the ordinary, day-by-day life of characters such as these, but it needs to do more than that.) It’s filled with shots of people sleeping in hammocks strung up within the farmhouse that’s its central setting; and long before it closes you might be inclined to doze off, too.