Bring kids. Anybody's kids. You'll have a better time.

I brought three rowdy, preteen Jack Black fans to "Nacho Libre." Good thing. They were delighted by every pratfall; each instance of Black mugging for the camera; and lots of extraneous, scatological stuff.

Without their exuberance, I could have easily sunk into abject despair.

"Nacho Libre," which opens at midnight tonight at several theaters, is one of those movies that makes you wonder what happened to a sure thing. It's the second feature by Jared Hess — whose "Napoleon Dynamite" was one of the best films of 2004 — and looked in trailers to be even more culturally loopy than the vacuum of "Napoleon's" Preston, Idaho.

It is loopier. But it's also more superficial, one big joke referencing the strange phenomenon of Mexico's masked-wrestler movies and the dampening effect of too much piety on the human spirit.

Where there was nothing satirical about Napoleon — the geeky hero was genuinely suffering from being self-referential in a larger world he couldn't understand — Black's Nacho, a cook in an Oaxacan monastery-orphanage, is a caricature of religious docility at war with machismo.

His testosterone surging with the arrival at the priory of a beautiful nun (Ana de la Reguera), Nacho becomes a masked wrestler with a secret identity.

Along with tag-team partner Esqueleto (Héctor Jiménez), the ample champ gets slaughtered every week fighting feral dwarves and sundry brutes.

For the most part, the film is a succession of sight gags and Black's impressive gallery of funny expressions for looking stirred by calls to greatness.

Some things work well, but many are strained in execution. There are times "Nacho Libre" looks like it's struggling to find a reason to continue.

So what happened? One thing that looked so promising was a script co-written by Mike White, who delivered a terrific hit for Black in "School of Rock." It now appears his sensibility and Hess' didn't mesh so well.

One can still see Hess' touch, especially in the listening-to-angels expression on so many faces (think Pedro in "Napoleon"). But, in the end, this Nickelodeon co-production is really an impersonal film for children who will see Black in anything.

Tom Keogh:

tomwkeogh@yahoo.com