Like Knocked Up and Superbad, Pineapple Express infuses a less-than-serious premise with genuine warmth without sacrificing the slightest bit of absurdity or humor. Dale Denton (Seth Rogen) inadvertently gets caught witnessing a murder while high, and can only think to turn to his pot dealer, Saul Silver (James Franco), for help. The widely-watched red band trailer gives the essence of the plot - stoner comedy meets action flick parody - but conceals just how ridiculous the movie is going to get. (The censored green band trailer, a friend observed, makes all weed references so oblique that Denton and Silver just seem retarded.)
The main draw is the unlikely pairing of stoner comedy and action flick parody, although transition is a little ragged. The first half definitely contains some pure pothead comedy that might be lost on those with no knowledge of drug culture. Sure, Franco's been sporting dimmed eyes his whole career (it may even be method acting, as anyone who's seen this interview can attest,) but he also perfectly hits all the stoner tropes. Saul's cross-joint is the pinnacle of stoner engineering by those who've smoked so much they look for increasingly complicated ways to toke. Dale's bit about the psuedo-friendship between customer and dealer is perfectly articulated in Saul's desperate guilt-tripping to get Dale to linger after the deal - "We could watch some crazy videos on the Internet!" - is spot on. Especially great is Saul's off-the-cuff listing of his favorite civil engineers. Pineapple Express, like Harold and Kumar, is fully aware that stoners can be doctors and scientists, not just slackers and dropouts.
But while Dale and Saul stumble through the second and third act blazed, sure, Pineapple Express does seem to lose sight of its aesthetic when it trades hot-boxing for Hot Fuzz. It's the chemistry between Rogen and Franco, reunited onscreen for the first time since Freaks and Geeks, at the heart of the film, not the plot. They're funnier on the run from the bad guys speculating than they are in the climactic gun battle, which works on a different level because it's structured exactly like a real action movie's finale would be: at a hideout, with all the characters combining to fight, and the baddies getting picked off one-by-one. On that note, special mention should be made of the hitman Matheson (Craig Robinson, best known as Darryl on the Office,) the only funny villain by both script and Robinson's performance.
It's also possible that some might point to gaps in logic in the story, but most of them are nods to shoot-em-up screenplay structure. Dale's subplot with his high school girlfriend makes as much sense as any tacked-on romance in an action flick, and her complete absence from the denouement points out how arbitrary that role is. It also leads to one of the film's best silly jokes, when Dale hurries her family into their car and suggest they check into a motel under a fake name, pauses, looks around himself, and comes up with "Garagely." Saul may even top this with the world's best drug dealing aliases: "Santiago and Dunbar."
But in the end, the film closes not with an explosion, a kiss, or a celebration, but with guys sitting at breakfast, recounting the tale and vowing to be best friends, and their relationship buoys the action. The black-and-white introductory flashback scene, which details secreet military testing on marijuana and an unscientific reason why it have have been banned, is cute, but feels ultimately pointless without Dale or Saul. The brief period when they are separated is also less entertaining. Pineapple Express is funniest when the dialogue is something that you'd hear from a zozzled friend while lounging on the living room couch.