You may think you know David Cross, but you have no idea.

Cross, a hipster/alternative comic who achieved cult fame on HBO’s “Mr. Show with Bob and David” in the late nineties, has been slowly seeping into mainstream culture. With bit parts in “Scary Movie 2,” “Ghost World,” and “Men in Black 2,” Cross – who was once described by his comedy partner Bob Odenkirk as being “violently bald” – is a spectacled chrome dome who gets ambiguously recognized as “Oh, that guy who was in that one movie.”

But while Cross’ day job may be making cameos in crappy sitcoms and lousy movies, his after-hours gig of terrorizing nightclubs with his biting stand-up act is well documented in a new DVD titled “Let America Laugh.”

“Let America Laugh” is being released by Sub Pop Records, who are more noted for the grunge explosion than stand-up comedy, and it is a perfect companion piece to Cross’ live comedy album “Shut Up, You Fucking Baby,” which the label put out last year. However, “Let America Laugh” focuses less on Cross’ stand-up act and instead shows the backstage hijinks and post-show parties of his 2002 tour.

The DVD begins with Cross telling director Lance Bangs (“Jackass: the Movie”), “I am going out on the road again, and what I want you to do is follow me around with that goddamn camera of yours.” The premise couldn’t be simpler as Bangs films Cross berating hecklers and partying with his fans. At a gig in Memphis, Cross receives a bizarre invitation from a fan that reads, “Come to Black Lodge Video – you will understand!” Cross and his crew show up at the video store at 1:30 a.m. and party with a group of stoners that resemble the motley crew of slackers that frequent Java Jones.

Cross’ jaunt through the Deep South provides the DVD’s funniest moments. At a club in Nashville, Cross accosts the club’s owner, T.C., during his act. After the show, T.C. barges into Cross’ dressing room and barks, “I want you out of my club! You can’t stand onstage in front of 400 people in my hometown, in my fucking house, and insult me!” Instead of leaving the club, though, Cross stays backstage for 35 minutes, pretending to play with his backpack. This uncomfortable moment perfectly captures Cross’ knack for finding the humor in acting like an asshole to unwitting buffoons.

Cross may be the funniest asshole on today’s comedy circuit, but his real talent lies in humorous social commentary and pointing out the stupidity of his fellow Americans. At a gig in Atlanta, Cross shows the audience a poster for a new “hippified” food product called Squagels. “Try Squagles! Square bagels! Finally! Don’t be oppressed by the tyranny of round, man. That’s bullshit! Your generation has a new-shaped bagel!” Cross rips into the ridiculousness of American life with massive amounts of sarcasm that make other sarcastic comics, like David Spade, look tame by comparison.

After following Cross through the South and the Pacific Northwest, the film concludes with a performance in Los Angeles, where Cross is reunited with his showbiz friends. But when placed in the fishbowl society of L.A., Cross makes it clear that he is disgusted with the Hollywood scene. “L.A. is the only town where I have millionaire friends who call me up and they’re like, ‘Hey, I desperately need two tickets to the show,'” Cross says. “These people are fucking millionaires!” The L.A. show also reunites Cross with Odenkirk, who declares, “David really turned the House of Blues into the House of Jokes!”

If you’re unfamiliar with the comedy of David Cross, “Let America Laugh” may be a bit of a rough introduction. For a better sampler of Cross’ outstanding comedic work, check out “Shut Up, You Fucking Baby” or “Mr. Show with Bob and David.” But if you’re looking for a behind-the-scenes glimpse of our nation’s funniest asshole, “Let America Laugh” will do just that.