Four children line up on the stairs in the front hallway, waiting. The housekeeper comes to the landing, cradling the baby on her hip. The doorbell rings. “Smile,” mom tells them, “and make the baby sitter feel welcome.” Eight-year-old Lulu (Morgan York) answers the door, sees Navy SEAL Shane Wolfe (Vin Diesel), screams and quickly slams it.

For the next hour and a half, The Pacifier continues this brigade of quirky comedic scenes. It’s the jokes, not the plot or the acting, that will keep you from walking out of the theater. While you’ll wonder how Diesel went from XXX to a PG-rated Disney film, you can’t help but laugh at the ridiculous situations and cheesy lines. You’ll only cock an eyebrow when Diesel’s Wolfe tells the kids “It’s done my way! No highway option!” but you’ll chuckle when Helga, the housekeeper (Carol Kane), whispers “You hov license to keel? Too baad, could come in handy,” in her smoky Romanian accent.

Wolfe leads his squad of SEALs in a top secret mission to save daddy Dr. Howard Plummer (Tate Donovan) and his government computer program from a foreign foe. If it sounds like a bad Mission: Impossible rip-off, that’s because it is. The plot follows the usual spy formula, with Wolfe whipping million-dollar government gadgets out of his pocket in the nick of time. Plummer gets whacked in the first five minutes, and Wolfe is sent to protect the Plummer family while Mrs. Plummer (Faith Ford) leaves town on top-secret business.

The baby-sitting spy is an interesting twist to a clichéd plot. At first, Wolfe is greeted with expected hatred from the kids and the housekeeper, none of whom want to make his job any easier. He, of course, wins over everyone with bits of advice and support. When Lulu and her fellow Girl Scout look-a-likes are beat up by a bunch of Boy Scouts in a West Side Story turf war saga, Wolfe teaches the girls vicious kung fu moves. The highlights are Wolfe singing and dancing the “Peter Panda Dance” and kicking the crap out of the assistant principal.

As far as the acting goes, all the characters are pretty much cardboard cutouts from other films. As with his other films, Diesel nails the role of the meaty action hero — an impermeable wall of flesh who spits clichés such as “Not on my watch.” But his soft side seems forced, and scenes that could have been tearjerkers are just plain sappy.

On the other hand, Kane nails the role of the dark, Romanian Helga. Her strange clothes and snake-like movements make her a delightfully witchy housekeeper. Helga’s quick, smart-aleck lines and gestures are some of the best The Pacifier has to offer.

Nothing about oldest daughter Zoey (Brittany Snow) or eight-year-old Lulu is anything special, but Max Thieriot’s punkish 14-year-old Seth is one of the few side characters who can keep your interest.

The Pacifier won’t win any Oscars next year, but it doesn’t suck either. Don’t go for the action, don’t even go for the story. Go for the novelty of seeing Vin Diesel trade his wetsuit for a baby carrier, drive a mini van (complete with “World’s Best Mother” bumper sticker) and attack ninjas with toys.