Johnny Knoxville is the kind of guy everyone likes. Girls want to smooch the wickedly handsome, 31-year-old prince of pranks, who plays a moronic alien in Men in Black II.

And guys want to see the former host of MTV's Jackass swim in sewage and get whacked in the crotch with paint balls. 

All he wants is a chance to rest his head, which got a serious whupping during the filming of Jackass: The Movie, to be released in October. 

"I have vertigo from it," he says. "I was knocked unconscious three times during filming. 

"That makes it, like, six or seven concussions in the past two years. If I put my head a certain way or lay down, the room spins. 

"I feel like Kim Novak!" 

Talk about head cases  Knoxville (real name: Phillip John Clapp) has two of them in Men in Black II

His character is a kind of Siamese twin; Knoxville plays both the alien Scrad and a smaller, computer-generated head, Charlie. 

Of course, the gutter-minded kid inside Knoxville can't resist the chance to riff on the double-entendre inherent in this premise. 

"Oh yeah, the little head," he drawls. "Makes every decision. He's definitely in charge." 

If you've never heard of Johnny Knoxville, chances are you haven't seen anyone staple his buttocks together, dive head-first into a pool of elephant dung or get slapped in the face with a wet salmon. 

Such pranks made him a gross-out god on "Jackass," which debuted on MTV in October 2000 and became an instant hit, with a weekly audience of 4 million viewers. (You can still catch reruns.) 

More often than not, Knoxville or one of his deranged sidekicks would finish up naked in a neighbor's yard. 

Knoxville promises Jackass: The Movie will be "the show times 10," and, to prove it, he runs through the stories behind his multiple concussions. 

The first one came after a golf cart he was riding in flipped and drove his head into the ground. 

"It was almost a snuff film," he says. 

Then, he went mano e mano with a super-heavyweight boxer at a swap meet and came off second-best. 

"I hit the cold hard floor and my head just bounced," he recalls. "I got six or seven stitches and a really bad concussion." 

The third concussion, a result of being "choked out" by a kung fu master, didn't make the movie  his drooling and convulsing was deemed too disturbing. 

Maybe that will make the director's cut  along with some other scenes that had to be cut to knock the movie down from an NC-17 rating to an R. 

Paramount is extremely high on Jackass: The Movie, saying the film's rating with test audiences has been through the roof. 

Barry Sonnenfeld, who directed him on MIB II and this spring's Big Trouble, believes Knoxville has got what it takes. 

"His acting ability goes way beyond Jackass, " Sonnenfeld said recently. 

Don't be surprised to see Knoxville — married dad of a 6-year-old daughter — use his heartthrob looks to catapult him out of the toilet. 

"I want to do comedy still, and I want to step out front," he says. 

"I'll take leading roles down the line." 

And there's good news for salmon the world over — he may even try to go serious. 

"I'd like to do some dramatic roles as well," he says, "but that's wide open for me."

For more news, entertainment and sports coverage, click here for NYPost.com.