Not a perfect ‘bromance’

The formula is pretty familiar by now in these Judd Apatow-produced comedies: A couple of buddies get into trouble, and as they try to bumble their way out of it, their friendship only grows stronger.

Some clever linguistics guru somewhere even came up with a word for this pop-culture phenomenon: the “Bromance.”

“Pineapple Express” tries to breathe some fresh life into this comic genre by turning it into a serious action movie. But because it tries to be both, it doesn’t completely work on either level.

Seth Rogen and James Franco have great chemistry, though, as our half-baked heroes – not surprising, since they’re both longtime Friends of Judd who co-starred on his TV series “Freaks and Geeks.”

This time, Rogen plays a vaguely more functional version of his “Knocked Up” slacker. His Dale Denton is a process server – he has to wear a tie, this must mean he’s a grown-up now – but he’s still dating a high-school hottie (Amber Heard) and his main priority is making frequent trips to his pot dealer.

That would be Franco’s character, the affable space cadet Saul Silver. It’s a wildly different role for the actor, best known as the pretty-boy bad guy in the “Spider-Man” movies and for his star-making, TV-movie turn as James Dean. Here, he’s just goofy and easygoing, prone to non sequiturs but sweet and instantly likable.

And he takes pride in his work. Saul sells an inordinately strong strain of weed known as Pineapple Express, one that’s so famously rare, he says smoking it is “like killing a unicorn.”

But because it’s so identifiable, it gets him and Dale tangled up with a dirty cop (Rosie Perez) and a homicidal drug lord (Gary Cole).

“Pineapple Express” is at its best when it’s about these two guys getting to know each other by talking about absolutely nothing. But then it goes off the rails and turns into a very generic action picture, full of fist-fights and shootouts and explosions, in what seems like an effort to be as broadly commercial as possible.

There’s a slightly slapsticky element to all this, but even that doesn’t make such mundane material any more compelling.

Still, maybe all of this is more fun if you’re under the influence of the same substance our stoner heroes are.

Not that we’re condoning that kind of activity, mind you.