Israeli Special Forces soldier Zohan is tired of war and just wants to cut hair for a living. So he fakes his own death, changes his name to Scrappy Coco and moves to New York. He tries unsuccessfully to get a job at the Paul Mitchell salon and has to look elsewhere for a job as a hairdresser. As he explores the city he discovers the Israeli and Palestinian population is split between two sides of the same street. Zohan finally gets a job in struggling Palestinian salon run by the beautiful Dalia. He soon graduates from sweeping the floor to styling hair, gaining a reputation amongst the local ladies. But soon Zohan's sworn enemy The Phantom is on his tail.

Had I known his film was directed by the man responsible for the execrable "I Now Pronounce You Chuck and Larry" I would have given it an exceptionally wide berth. Sadly I was sucked in by the slapstick shenanigans of the trailer, much to my chagrin. Dennis Dugan seems pathologically incapable of shooting comedy. He has no comic timing to speak of, allowing jokes to go on too long or repeating the same gag long after it has ceased to be funny. This is especially true of Zohan's propensity for catching things between his buttocks and his habit of sleeping with his elderly hairdressing clients. Often the pauses between a gag and its punchline is far too long. The director fares better when he is treating the film as a spy movie or thriller parody, as in an early chase scene that apes the parkour pursuit through Tangiers in "The Bourne Supremacy". Perhaps if he had stuck to parody rather than impressing a tired fish-out-of-water narrative over the top, then this would have been a better movie. The funniest bits would be those where Zohan's army background impinges on his work as a hairdresser, were it not for the fact we'd seen them in the trailer.

It is telling that the best bits of the film are those that are free of its star, suggesting that Dugan is beholden to his leading an and where he goes, the helmer will follow, regardless of whether the tangent is warranted or funny. Maybe if the director cared more about his characters it would help, but it feels like everyone is there to prop up Adam Sandler. The majority of the running gags don't work because the initial premise isn't amusing enough. What's the obsession with houmous about? Okay, it may be a Middle Eastern dish, but watching an elderly man dunk his specs in it and eat it or add it to his coffee isn't that funny. Other jokes feel like poor taste, such as playing hacky-sack with a cat. The stunt work is better accomplished, showcasing some acrobatic parkour and solid stunt driving and the pyrotechnics employed are impressive. It's a shame they aren't attached to a better film. There aren't enough jokes to keep the movie ticking along, so it feels overlong at a hundred-and-thirteen minutes.

The screenplay by Adam Sandler, Robert Smigel and Judd Apatow is sketchy on characterisation and high on lowbrow humour. One of the major problems is that it doesn't fit comfortably in any comedy sub-genre; part spy movie parody, part culture clash and part romantic comedy. By trying to be the servant to so many masters, they end up pleasing none. It makes the film episodic and there are crunching gear shifts between the three styles. In an attempt to paper over the cracks, the writers have introduced a series of gags that can be relayed in montages or as running jokes. These include Zohan going to job interviews and screwing up as his special forces training kicks in, his overzealous sweeping up at Dalia's salon and the long line of hairdressing clients he sleeps with. There are knob gags at every turn that aren't that funny to begin with and become less so with every repetition. There are a couple of stabs at dealing humorously with the Israeli-Palestinian conflict, but it is merely touched on and then ignored, as if the writers don't have the bottle to face it head-on. There is also a streak of sentimentality running through the movie that is at odds with the gross-out aspects of the film.

The characterisation is flimsy to say the least. We don't see enough of Zohan as a soldier and his celebrity seems to be based more on his prowess at hacky-sack and tug-of-war than his abilities in war. So we lose a great deal of comic potential from the outset as his transformation to hair stylist hasn't got much to be contrasted with. He's just not that interesting or sympathetic, especially as he spends most of his time having sex with elderly women for no apparent reason or trying to make houmous an all-purpose item. Dalia is a bland love interest and The Phantom is a toothless villain who is discarded for much of the film. He is then replaced by corporate bad guy Walbridge who appears even more impotent. Meanwhile the Palestinian and Jewish characters are either faceless or stereotypes. The dialogue is pitiful, using fake Hebrew to try to get laughs, which doesn't work because adding a guttural "ach" to the end of words isn't funny. There is a dearth of good lines, the funniest you get is Zohan's father telling him "You're like Rembrandt with a grenade." Instead we are subjected to a plethora of knob jokes that are too frequent to raise a smile.

Adam Sandler is definitely losing his edge in the comedy stakes. He seems to have lost the ability to create characters an audience will care about like Robbie Hart in "The Wedding Singer". In his hands, Zohan is a one-trick pony; a bad haircut with a thick accent and the habit of trying to hump anything that moves. He doesn't have enough personality for you to like him and Sandler's timing is off so he isn't funny. As a result much of the slapstick and gags fall flat.

John Turturro is dreadful as The Phantom, spending most of his time shouting and jigging about as if he had Saint Vitus' dance. It's hard to decide whether his accent is better or worse than that of Rob Schneider, who pops up as Palestinian taxi driver Salim. The most you can say for him is that he's lost a lot of weight, the worst is that he can't act and thinks it appropriate to black up to play an Arab character. Emanuelle Chriqui at least looks the part as Dalia. She's pretty and fiery, but the shortcomings of the script leave her as nothing more than a bland love interest. Meanwhile Nick Swardson is vaguely camp as Michael, but the only thing you'll remember about him is his ginger pubic perm. But even that is better to watch than the none-more-plastic Mariah Carey who seems to have had so much work done she is incapable of expression. It's pretty damning when you can't even convince playing yourself.

The original music by Rupert Gregson-Williams struggles to be heard amongst all the other soundtrack choices. It seems to boil down to a few arrangements of loose, jangly guitars with strings, Jewish horns and ethereal vocals and some Bond-style electric guitar and brass and strings for the super-soldier segments. The salons are represented by wistful flutes and clarinets. Otherwise the soundtrack comprises of some naff-sounding Israeli hip-hop, the cheesiest version of Alphabeat's "Fascination" you've ever heard, "I Wanna Sex You Up", the Stereo MCs' "Connected", "Pump Up the Jam", a version of the "Rocky" theme tune played on Middle Eastern instruments and plenty of Mariah Carey. It doesn't really hang together as a body of work, so I suppose it fits the rest of the film.

"You Don't Mess With the Zohan" is a dreadful stab at comedy that fails utterly for one very simple reason; it isn't funny. This is as a result of lacklustre direction, poor writing and bad performances. I think Adam Sandler has to shoulder much of the blame as he wrote and stars in it and the director is clearly pandering to him. I would advise you to stay away from this movie as if your life depended on it, lest it infect you with its bad jokes, so you start to think Rob Schneider or Adam Sandler's backside (which appears so often it probably has its own agent) is funny.