American Ultra is, to pardon the unintentional pun, a half-baked stoner-action comedy. The flashy, genre-bending sleeper agent movie desperately hopes to become a sleeper hit among the couch-ridden, bong-hitting slackers of America, and it does have a lot going for it. The actors are admirably dedicated to their characters, the action is constant — and quite gory, for that matter — and there’s always a clever joke or two available at a moment’s notice. The gun-enthused, dirty-mouthed, blood-squirting, smoke-dazed rom-com comes across like a 14-year-old pothead boy’s cinematic wet dream, and it’s a little smarter and a lot more sensitive than whatever his active imagination would doodle in his worn-and-torn notebook. If only it were more confident about itself.

Much like our lead, Mike Howell (Jesse Eisenberg), the latest film from Nima Nourizadeh (Project X) is a fidgety and often-apologetic copulation. Its irreverence only comes at a point, and it doesn’t provide anything beyond what people have already seen before, and seen better — yet, as stressed before, American Ultra doesn’t completely squatter its potential either. It’s a dope comedy that’s not completely dopey, but it always feels like it could be a lot cleverer, especially when you know it's a screenplay by the naturally, wicked talented Max Landis (Chronicle). It’s a little too dazed and confused for its own good.

It centers on our anxiety-ridden stoner as he burns his days away as a cashier at a dead-end mini-mart in Middle America. Supported by his overly forgiving girlfriend Phoebe Larson (Kristen Stewart), he cannot imagine his life without her. Literally. His memory fails to recollect anything before their relationship began, and his partner never bothered to ask about his parents, his childhood or anything about his past. He doesn’t understand why she wouldn’t be curious but, then again, he’s never searched too far into her history. So he’s not one to complain.

He may not know much, but even he knows she’s the best thing that will ever happen to him. Having purchased the “perfect” ring, he plans to muster up the courage to propose to her … sometime. He’s still trying to figure out the right time. His inability to profess his love, and worrying if he’s truly right for her, clouts his simple mind as he spends his days minding the register and drawing his comic creation, Apollo Ape. But soon he’ll have bigger problems to deal with. When C.I.A. correspondent Victoria Lasseter (Connie Britton) pays him an unsuspecting visit at work, he quickly finds his mind awakened to super-reflexes he never knew he possessed, as well as information he never thought he’d possess.

And it couldn’t have come at a better time, for when tons of bad guys find themselves pointing guns at his face he’s speedy as a bullet to wipe them out one-by-one. His macho and super-swift abilities are beyond his comprehension, like everything else in his life, but Phoebe remains by his side as always — even when Lasseter’s higher-up Adrian (Topher Grace) refuses to let the couple live throughout the night without a fight. It’s Pineapple Express, True Romance, The Bourne Identity and Burn After Reading rolled together into a greasy, weed-laced omelette, though the recipe isn’t as satisfying as the individual ingredients.

It’s proud not to conform into one specific tone, but it’s not sure-handed enough in its approach to make it all come together smooth or collected. With that said, its insecurities do mildly end up in its favor. There’s a sweet vulnerability brought in through Eisenberg’s sweet-natured performance, supported by the genuine chemistry he shares with his Adventureland co-star Stewart. Their romance is touching and filled with odd poignancy, giving Nourizadeh’s film a beating heart at the center of its bloodshed and general mayhem.

When American Ultra focuses on their relationship, it resonates. Mike and Phoebe don’t necessarily feel like the “perfect f**ked-up couple,” as they describe themselves, but their love definitely shines through. Stewart, in particular, glows even brighter than Eisenberg, feeling completely at home here with her faded red-haired every-girl and makes the role entirely her own. With the characters spending most of the running time fighting baddies, dodging bullets or speeding away from cars driven by literal maniacs, however, the humble deadbeats’ romance often takes a backseat. Landis’ voice is as vibrant as always in their most tender scenes together, but it doesn’t get the opportunity to sing as loud as usually does admit the madness of his mashed-up story.

Their earnest work also isn’t benefited from Nourizadeh’s inability to decide whether or not to ground American Ultra closer to reality or own up to its cartoony nature. Nor is it bolstered by Grace or John Leguizamo, as Mike’s eccentric provider Rose, whom individually try far-too-hard to steal every scene they’re in. They're overblown performances often take time away from the real standouts of the film as well: Tony Hale, as Lasseter’s one-time assistant Petey and Walton Goggins as the psychopath known solely as Laughter. Again, it's by no means a complete failure. The film is well edited, finely paced, good-spirited and occasionally funny, but it’s also a jumbled and bumpy. It never decides where it should take itself and ultimately goes for the scattershot approach, and it’s also killed by a super-speed rewind in the first three minutes that spoils its own ending and extracting any tension it would’ve maybe earned. There’s a lewd, funny comedy almost bursting out here, but it never comes into fruition. It’s potential isn’t completely smoked; it’s just not entirely lit up.