In the last six years, the Wayans brothers (namely, writer-director Keenen and writer-actors Marlon and Shawn) have hit the jackpot in Hollywood, making thin-as-a-rail, purposefully stupid comedies with one-line premises so off-the-wall they have caught the attention of a certain mainstream audience segment. 2000's "Scary Movie" and 2001's "Scary Movie 2" were raunchy horror movie spoofs. 2004's "White Chicks" was a raunchy flick about two black undercover agents who pose as wealthy, lily-white heiresses in the Hamptons. The Wayans' latest mind-numbing venture involves a criminal, sex-hungry little person being mistaken for a toddler by a childless married couple. To say it's raunchy and that it treads dangerously close to overstepping its PG-13 rating is a given.

Vertically challenged thief Calvin (Marlon Wayans) has scarcely stepped off the prison grounds before he begins plotting his next scam with dimwitted partner Percy (Tracy Morgan). After successfully stealing a valuable diamond from a jewelry story—and with the cops hot on their trail—Calvin gets rid of the evidence by dropping it in the purse of Vanessa (Kerry Washington). In need of getting the diamond back, Calvin gets an idea so crazy it just might work: act the part of an abandoned baby, get taken in by Vanessa and husband Darryl (Shawn Wayans), and snatch the jewel back when no one is looking. Sure enough, Darryl and Vanessa, who have no children of their own, fall head over heels for Calvin and take him in. Making off with the score, however, is going to be much easier said than done.

About the best thing that can be noted about "Little Man" is that it could have been far worse and more painful than it is. The basic plot is indescribably moronic—a vast suspension of disbelief is required for a movie in which every single character instantly accepts that plainly adult little person Calvin is actually a two-year-old—but director Keenen Ivory Wayans does squeeze a few solid chuckles out of the clothesline material. True to form, the comedy in "Little Man" is exceedingly predictable, scatological and full of cheap shots, its sheer shameless juvenilia ranging from horribly unfunny to outrageously zany. If one wants to dig deeper, it's also racist of white people and prejudiced against little people, the latter irresponsibly viewed here as childlike just because of their size and no matter their age.

A string of dumb jokes and a minimum of story was all that was needed in the first two "Scary Movie" pictures because rapid-fire, self-referential gags being pummeled at the viewer was the whole point. Due to the fact that "Little Man" isn't directly spoofing anything and is set in a world approximating real life, a little more story and character meat is required to withstand a 98-minute running time. This is where the film egregiously falters. Plot threads are introduced and then forgotten about, while cartoonish characters come and go at random, few of them given the time to distinguish themselves beyond one personality trait.

A series of barely connected skits is acceptable on a variety show, but being offered too long a dose of such leads to monotony by the end of the first hour, and utter insufferability by the climax. As the set-pieces of sexual (it's implied that Vanessa, believing him to be Darryl, has sex with Calvin), violent (a blatant rip-off of the out-of-control football scene in "Wedding Crashers") and toilet humor (a fart so loud and thunderous that the theater auditorium shook) stack up, the energy level gradually deflates until it is nonexistent. Simply put, there isn't a character to get properly attached to, a relationship to take seriously, or a narrative involving enough to care at all about the outcome.

As Calvin, Marlon Wayans mugs in front of a green screen, his head planted oddly on a little person's body for the duration. This visual effect is clumsily rendered some of the time and fairly convincing the rest. Wayans has little dialogue since he is supposed to be acting like a toddler in front of his would-be adoptive parents, but does get a few laughs from the dirty thoughts read from his mischievous facial expressions. Shawn Wayans and Kerry Washington (2004's "Ray") are likable as the earnest Darryl and Vanessa, even if they are ask to play comparative straight men to Marlon. The two most memorable turns come from cameos, one from David Alan Grier (2005's "Bewitched") as an intrusive restaurant serenader, and the other from Molly Shannon (2006's "Scary Movie 4"), a hilarious standout as a soccer mom who takes multitasking to a whole new level.

Made on a low budget or just seeming that way, "Little Man" is visually underlit and bumblingly edited. Scenes don't draw to a conclusion so much as they run out of inspiration and just end at random. The same could be said about the film itself. "Little Man" is the equivalent of thriftily priced junk food set out in the sun too long; it tastes okay at first before a rancid stench takes over that leaves you wanting to flee to the bathroom. All that is left are memories of a bad time and regrets that you ever decided to eat in the first place.