“Pineapple Express” thinks it knows what we want in a Seth Rogen film - the burly comic swapping punches with a cold-blooded killer.

Confused? Join the crowd.

“Pineapple Express,” from the Judd Apatow assembly line, seriously misjudges its star’s lumpy appeal and the limits of our comedic tolerance. Rather than whip up a stoner comedy worthy of Cheech and Kumar, it devolves into a shoot ‘em up that would make Quentin Tarantino blush.

Yet neither the stoner antics nor the ultra-violence save the film.

 

Rogen stars as a process server named Dale who lives to light up. One day he witnesses a murder while staking out a client and flees the scene, leaving a stash of one-of-a-kind pot behind. He scrambles to see his dealer, Saul (a moist-eyed James Franco), because he fears the killers are tracking him and his unique purchase.

What comes next is alternately amusing and dull, but feel free to add a star if you’re under any influence.

Franco, casting aside his good looks, steals what’s worth stealing here. Rogen wears out his welcome by mid-film, though, precisely when the “Express” heads into “Rambo” territory.

Why a stoner comedy must become a Tarantino-style blowout mystifies. The film’s tone, a tapestry of ill-fitting moods, takes a final turn for the bizarre in the last 20 minutes. Bullets fly, cars crash into buildings and we’re left with the wreckage of what might have been a serviceable stoner comedy, a genre seriously lacking in quality.

“PIneapple Express” wants to have it every which way. It celebrates getting high, until a key character bemoans how much trouble being stoned has caused. At one point, Saul sells pot to some pre-teenagers, a throwaway moment that’s as irresponsible as it is unfunny.

And the film could easily be trimmed by 20 minutes without losing a beat.

“PIneapple Express” should have been combined Apatow’s comic instincts with the venerable stoner genre. Instead, it leaves audiences anything but high.

DID YOU KNOW: Seth Rogen, who openly discusses his pot use with anyone who will listen, claims the current strain of marijuana known as “pineapple express” didn’t exist until his 2008 movie of the same name.