Do you remember how disappointed you were when it turned out that Maggie Simpson had shot Mr. Burns, or you learned that the 1985-86 season of “Dallas” had been nothing but a bad dream? You’ll probably experience much the same letdown at the close of James Mangold’s highly Freudian reworking of that old Agatha Christie chestnut “Ten Little Indians” (which a character even refers to at one point–though there’s a dash of “Murder on the Orient Express” here, too). “Identity” is like a slickly-produced puzzle whose pieces fit together just fine, but when completed depicts a scene not worth looking at. When the last-minute “twist” rolls around (it wants to be as suddenly shocking as that in “Carrie,” but fails), you’re likely to feel cheated rather than happily misled. (Compare a film like 1973’s “The Last of Sheila,” written by Stephen Sondheim and Anthony Perkins, of all people, which is equally complicated but satisfyingly so, or even the more recent “Primal Fear,” which was nothing more than a psychological updating of Christie’s “Witness for the Prosecution,” but one that came off much better than this.)

The elaborate set-up traps a bunch of travelers at an isolated, Bates-like motel on a desolate stretch of Nevada highway during a stormy night (flash floods prevent them from leaving, and of course all the phones are out). There’s milquetoast George (John C. McGinley), whose wife Alice (Leila Kenzle) has been seriously injured in an auto accident and whose young stepson Timmy (Bret Loehr) is traumatized by the tragedy. And Ed (John Cusack), the ex-cop turned chauffeur who struck Alice while driving Caroline Suzanne (Rebecca DeMornay), a shrilly demanding over-the-hill actress, from her latest location. And Paris (Amanda Peet), a hooker traveling from Las Vegas to her native Florida to buy an orange grove with her hard-earned stash, whose spiked shoe, carelessly tossed onto the road, actually caused the blowout that put Alice in the path of Ed’s limo. And squabbling white-trash newlyweds Lou (William Lee Scott) and Ginny (Clea DuVall). And volatile state lawman Rhodes (Ray Liotta), who’s transporting convicted killer Robert Maine (Jake Busey) to an unknown destination. Hosting them all is sleazy, fidgety clerk Norman–sorry, Larry (John Hawkes). Before long the “guests” begin dying in particularly gruesome ways, apparently in the order of their room assignments; and it turns out there are links among them involving names and birth dates. But there’s more: in a parallel storyline, a mass murderer about to be sent to his final reward is being brought to a special judicial proceeding, where evidence about his mental condition, provided by a solemn shrink (Alfred Molina), will determine whether his imminent execution will be stayed. One naturally assumes that the expected convict is Maine, but…. On the other front, things back at the motel come to a head when the bodies of all the victims suddenly disappear, and a suggestion that a nearby Indian burial ground might have something to do with it (“Poltergeist” redux) briefly surfaces. (To be fair, the notion does give rise to one of the script’s funniest lines, when Rhodes observes, “They’re all coming back to life like sea monkeys.”)

If all this sounds both absurdly intricate and intricately absurd, that’s because it is. But just when–a little over an hour in–matters have gotten so convoluted that you’d swear there’s no way out, Mangold and writer Michael Cooney spring a surprise that does, in fact, explain it all. The problem is that the revelation is not only a cheap trick, but makes it impossible to maintain any emotional investment in the fate of the surviving characters. Not that it was likely that you’d make a commitment to any of these cardboard figures to begin with. All the people here are types, a hack writer’s conventions, rather than flesh-and-blood individuals (a better title might be “Ten No-So-Little Red Herrings”), and even good performers can’t do anything but emphasize their obvious traits. (A cast list that includes such characters as “Naked Businessman” and “Frozen Body” is hardly promising.) The best work is done by Cusack, whose sad, boyish demeanor makes him easy to identify with (pun intended), and Peet, who fills out her scanty wardrobe well; but their success is entirely relative, and is countered by the scenery-chewing of the others–Busey (with his shark-like smile), Liotta (exuding rage), Hawkes (overdoing the hayseed bit), McGinley (with his repressed shtick), DuVall (whose hysteria borders on the farcical), Scott (drearily surly), and DeMornay (a caricature of the arrogant has-been). Molina underplays as the shrink, which is at least a change from the norm, and Pruitt Taylor Vince, of the perpetually roving eyes, shows up late on in a small but pivotal role. It remains to note that “Identity” has an appropriate cheesy feel, the way a modern analogue to a William Castle movie ought to do; the production design by Mark Friedberg (whose talents were put to far better use in “Far from Heaven”) is amusingly tacky, Phedon Papamichael’s cinematography emphasizes the darkly garish atmosphere, and Alan Silvestri’s score pumps up every nonsensical point. But while as an aspiring comic thriller “Identity” hits its lowbrow target in all these areas, overall Mangold has stinted on the comedy, failing to invest the piece with the panache required to raise this sort of creaky haunted house contrivance beyond the stage of overripe camp.

Anybody looking to investigate the template of “Identity” has plenty of choices. One, of course, is to go back to Christie’s original (its initial, now highly offensive title long having been retired), and actually read it. But if you prefer a film adaptation, avoid the various versions available under the “Indians” title (they decline in quality from fair in 1966 to poor in 1975 to absolutely awful in 1989) and seek out the best: Rene Clair’s superb 1945 “And Then There Were None,” with its crisp script, perfect cast and stylish direction. As for “Identity,” you might feel yourself strangely affected when Paris shouts at one particularly hysterical point, “I just want to grow oranges!” At the time the line is a guaranteed laugh-inducer, but you might just come to feel that nurturing citrus fruit would actually be a better way of occupying your own time than watching this glitzy but ultimately usatisfying movie.