Playing out like a series of skits from Mel Brooks' 1981 comedy "classic" History Of The World: Part I, director Harold Ramis' Year One has a slightly antiquated feel, riding a style of comedy far less cutting than recent gag-fests like The Hangover and Role Models. That's not to say, however, that it's not without its own peculiar charms, but the film is undeniably hampered by an occasional loss of energy and an over abundance of silly, obvious humour, with fart jokes the order of the day.

Jack Black and Michael Cera are two members of a primitive tribe of hunters and gatherers. Both too meek to make it in this group of alpha males, the boys are banished, and end up walking until they arrive in a considerably more advanced ancient community. They first meet bickering brothers Cain (Arrested Development's David Cross in particularly irritating form) and Abel (a disappointingly under-used Paul Rudd), before brushing shoulders with other Biblical figures, such as circumcision-happy Abraham (an appropriate character for perennial dial-a-ham Hank Azaria) and his son Isaac (Superbad's McLovin fails to make much of an impact), before finding themselves in the sexy "paradise" of Sodom (yes, cue plentiful back-door bandit-type jokes). There are other "plot" elements (including fairly tepid romantic interests and such), but that's not really the point here.

By now, we know that Jack Black and Michael Cera are pretty much the same in every movie, but that's what gives the slightly underwhelming Year One its primary comic kick. Their anachronistic dialogue and mannerisms - all delivered while wearing loincloths and silly cave man wigs - are continually amusing. Director Harold Ramis (Caddyshack, National Lampoon's Vacation, Groundhog Day), meanwhile, knows enough about comedy to keep things ticking over nicely. That said, there's something undeniably lazy and tossed off about Year One: everyone feels like they're cruising, rather than really firing up. It's reasonably entertaining (on DVD, we'd suggest, rather than at the cinema), but Year One is definitely not one for the ages.