C-

Almost everybody’s got amnesia in “Unknown,” and after watching it you might pine to be similarly afflicted. This is one of those puny little movies in which the makers hope that a bizarre premise will be enough to maintain interest in what amounts to a very pallid follow-through. But it isn’t, and it doesn’t.

The picture begins with five guys, all the worse for wear, waking up in a locked warehouse in the middle of nowhere with no memory of who they are or what they’re doing there. The first to awaken, and thus the functional audience surrogate, is a dark, moody fellow (Jim Caviezel, handsome but scruffy), who finds another fellow (Jeremy Sisto) shot and dangling by handcuffs from a trestle, a second (Joe Pantoliano) tied to a chair, and a third (Greg Kinnear) unconscious on the floor. The fifth man (Barry Pepper) pops up later, having been knocked out atop that trestle.

Eventually the men, all afflicted by memory loss (caused, they eventually discover, from a gas cannister apparently broken open during a struggle), conclude that a couple of them are kidnap victims and the others members of the gang. (The newspaper that tells them so, unhappily, doesn’t print any photos of the snatched men.) They also learn, via a phone call, that other members of the gang, led by a gruff chieftain (Peter Stormare), are en route back with lots of cash. Amidst considerable bickering they decide to work together first to escape the warehouse and, when that proves impossible, to prepare a hostile welcome party for the returnees. What they’re unaware of is that a couple of cops (Chris Mulkey and Clayne Crawford) are on their tail, and that the wife (Bridget Moynahan) of the kidnapped bigwig (the other man being his underling) has been involved in delivering the ransom.

Of necessity the picture is pretty much a gabfest, fashioned by scripter Matthew Waynee as a sort of “Usual Suspects” clone with Tarantino overtones. The structure has a sort of whack-a-mole quality to it, as each of the quintet gets the chance to deliver monologue-like riffs and then they double up to rant at one another or conspire against one another (a hint of the old “Diplomacy” board game here); and the efforts to generate suspense by inserting scenes involving a man and his boy who happen to stop outside the remote structure where the fellows are lodged or cutting periodically back to the cops or returning criminals, aren’t terribly successful. There’s also a final twist that’s almost a mirror image of the one in “Suspects,” but it barely lifts off, let alone flies.

The cast goes through the obligatory paces here. One can see why they were all attracted to the material, which gives each a chance to take center-stage with full spotlight for a few minutes and deliver ripe (indeed, overripe) dialogue. But none of them can invest their sketchily-written characters with any real depth. On the technical level there’s not much to report beyond a necessarily claustrophobic quality that will play better on cable than the big screen.

So “Unknown” is likely to remain that way.