On paper, it looks like one of those dream team comic duos. Having wild-eyed goofball Jack Black paired with master of understated delivery and awkwardness Michael Cera in the prehistoric comedy "Year One" sounds like a match made heaven. Unfortunately, on paper is where this idea should have stayed. Despite Black and Cera's abilities, "Year One" runs on the juice of rehashed historical parody and toilet humor with little laughs and zero cleverness.

In a primitive civilization, bumbling hunter Zed (Black) and insecure, sensitive food gatherer Oh (Cera) are struggling to find happiness. They are both practically outcasts in their village, and neither one can convince their caveman crushes Maya (June Diane Raphael) or Emma (Juno Temple) to be their mates. The two are eventually run after Zed decides to eat an apple from the forbidden tree of knowledge to change his fate. From there, the two somehow manage to stumblecircumstances and civilizations, running into Romans and Hebrews and encountering Biblical characters like Cain and Abel (David Cross and Paul Rudd) along with Abraham and Isaac (Hank Azaria and Christopher Mintz-Plasse a.k.a. "McLovin" from "Superbad") on their way to Sodom to rescue Maya and Emma from slavery.

Don't ask how or why all of these encounters happen across so many time periods in this loosely drawn plot. It's just an excuse to throw in a ton of recognizable faces, including the film's director Harold Ramis ("Caddyshack," "Analyze This") and Oliver Platt as a rotund homosexual high priest covered in makeup and jewels and sporting a wookie-like mane of chest hair. All of the actors do whatever they can to milk laughs out of this flick, but it's mainly Cera and Black who come through as zen masters of their own comic niches that nicely bounce off one another.

It would help if they had a decent story and jokes to work with. The uninspired screenplay by Ramis, Gene Stupnitsky and Lee Eisenberg screens like the Old Testament with fart jokes, touching on comic terrain that both Monty Python and Mel Brooks did way better. And most of the comedy comes in the form of bodily function and sex humor, which causes actors to resort to eating feces and urinating on their own faces (don't ask). And at 100 minutes, it's a lot to stomach.

Black and Cera's performances are "Year One's" only redeeming qualities. But even with their attributes, this comedy doesn't belong in any history book.