Harold Ramis has worked in comedy a long time, and his career has taken many directions. With his work on the Ghostbusters (1984) script and his straight-man performance in the film, he managed to allow Bill Murray room to move and riff within the confines of a visual effects-heavy summer blockbuster. As for the meticulously crafted classic Groundhog Day (1993), I hesitate to call any movie "perfect," but it comes close. But then there were phoned-in hits like Analyze This (1999) and Analyze That (2002) that seemed too tightly wound and too slavishly dependent on plot to be very funny.

Ramis' new film
Year One, on the other hand, comes closer to the spirit of his directorial debut Caddyshack (1980). I'm not saying it's quite as funny or as brilliant, but it's in the same spirit. It cares thankfully little about its plot or its character arcs, or historical accuracy; it's a bit flabby and careless, but it's also gleefully stupid, and it has the ability to knock you off guard and make you giggle helplessly.

Jack Black stars as Zed, an inept hunter in a primitive tribe of hunter-gatherers. His best friend is Oh (Michael Cera), a gatherer who forever endures jokes about his girlishness. Zed is in love with Maya (June Diane Raphael) and Oh with Eema (Juno Temple), but neither loser has enough going for him to promise them much. So when Zed eats from the tree of forbidden fruit, he is forced to leave and Oh tags along. (Subsequently, Zed believes he has been "chosen.") On their first stop, they meet arguing brothers Cain (David Cross) and Abel (Paul Rudd), and watch slack-jawed as Cain bludgeons his brother to death. Now more or less fugitives, they continue on, becoming slaves, escaping, meeting Abraham and stopping him from sacrificing his son, and finally venturing into the sin-ridden city of Sodom to rescue their girls.

Year One starts out with a couple minutes of ultra-serious Apocalypto-type footage, with tribal hunters stalking some prey in the jungle, before Zed bungles out and establishes the tone for the entire film. Basically, everyone speaks English, and modern-day vernacular and slang are allowed, even if references to modern-day inventions and developments are not. The eventual goal is for the two boys to become men and earn the hands of their beloved women, but the movie doesn't mind occasionally stopping for laughs in the pursuit of this goal. Unfortunately, if the gags don't work in these stopping places, the stop just feels like a lag, like a bit of fat that didn't get trimmed out. And indeed, we get the usual share of penis jokes, pee jokes and poo jokes that rarely work. (There are few sex jokes; they were reportedly cut out during an appeal to change the rating from 'R' to 'PG-13.') I laughed at one pee joke, but not because of the joke itself; rather, I laughed at Black's follow-up line: "I'm peeing on my own face, too... on the inside."

Black is a good reason why most of this works. (Back in 2000, I was convinced that Black deserved an Oscar nomination for High Fidelity.) Like Murray in Ghostbusters or Will Ferrell in his best films, Black has discovered a way to make it seem as if he's improvising all his lines in his own style. And his style is awfully hard to define; he's cocky and confident, yet not arrogant or overbearing. He's incompetent, but not useless. He's verbose but not obnoxious. His funniest lines can sometimes seem like the creation of an enthusiastic ten year-old or like the creation of a clever and witty playwright. It seems as if many up-and-coming comedians are trying in various ways to copy Black's brand of tubby energy, and failing (Dan Fogler comes to mind).

However, Black is surrounded in Year One by many other able comedians; Cera has a similar, rambly type of comic delivery, but sweeter and quieter, and he's a perfect match for Black. Ramis appears as Cain and Abel's father Adam, and Hank Azaria -- apparently capable of any voice or accent -- is Abraham, who is obsessed with circumcising every male within earshot. Oliver Platt is very funny as the lusty, effeminate high priest, and Cross makes an appealing maniacal Cain. And the great Vinnie Jones (The Midnight Meat Train), with his psychotic, soccer hooligan stare, plays a violent guard. To round out the comedy pedigree, we have screenwriters Gene Stupnitsky and Lee Eisenberg, from the American version of TV's "The Office" (on which Ramis also worked), and of course, producer Judd Apatow, who seems to collect a stable of comedians like a nobleman might collect prize steeds.

In the end, we get a reel of hilarious bloopers, which indicates how much fun the shoot must have been. It reminded me of a few other comedies, specifically things like Three Amigos, The Golden Child and Spaceballs, that critics aren't supposed to like, but somehow provide some guilty laughs anyway, mainly because of the comic energy that radiates from the screen. With all these different types of funny people butting heads all day long every day, something good was bound to come out of it.