"An amiable stroll through biblical times featuring Jack Black and Michael Cera as exiled Neanderthals," said Ronnie Scheib in Variety, Harold Ramis' Year One "elicits many mild smiles." The film is a "low-tech opus" that "offers an ironic commentary on the utter idiocy of religious superstition and received knowledge, all the funnier for being delivered by world-class idiot Black." (watch the trailer for Year One)

Jack Black and Michael Cera "share a loopy chemistry," said Michael Sragow in the Baltimore Sun, and "their affection is disarming—they keep the movie likable even when it stumbles all over the place and then gets stuck in Sodom." But if Year One "were a bowling match, it would lurch between gutter balls and spares, with some scattered lucky strikes."

Hardly, said Joe Neumaier in the New York Daily News. "Year One falls flat from its genesis to its outtake-filled credits scene, never moving beyond obvious setups or jokes that have been as beaten to death as Abel." The film really has no redeeming qualities—"talk about a disaster of biblical proportions."