The challenge in creating a cross-genre mashup is delivering a movie that manages to satisfy while going out of its way not to fall back on certain genre expectations. ‘American Ultra’ teeters on that very thin line throughout and comes out the other side reasonably unscathed. You can’t say the movie is perfect, but nor can you dismiss it as a messy failure.

For those who enjoy stoner comedies, earnest indie romance, paranoid thrillers and ultra-violence, it’s hard to imagine that you won’t find something to like here. Even if you hate one sequence, just wait a few minutes for the gears to shift and the movie will transform into something else.

Jesse Eisenberg stars as Mike Howell, a lost stoner misfit who lives his days in a daze and experiences panic attacks any time he dares to leave his tiny town. The only good thing that he has in his life is his girlfriend Phoebe (Kristen Stewart), who seems impossibly caring in that way that movie girlfriends tend to do.

One day, things go all topsy-turvy for Mike when a mysterious woman (Connie Britton) shows up at the convenience store where he works and mutters some bizarre code words. The next thing you know, Mike is unhinged. He’s still a sweetie-pie, only now the type of sweetie-pie who can name off fifty types of tanks at will and is capable of murdering trained assassins with simple household objects. It turns out that he was once part of one of those secret Jason Bourne-style government assassin programs and now he has to fight off waves of his former brethren sent out by Topher Grace, who secretly created the program and hopes to cover his tracks.

The script comes from Hollywood’s current golden boy screenwriter Max Landis, who caused waves with ‘Chronicle‘ and has three more movies on the way this year alone. It’s the type of wink-wink clever screenplay that likely kicked ass as a writing sample, but plays out only so-so as an actual film. Landis certainly has a knack for mixing tones. The early scenes bounce between soft-hearted indie romance and filth-flinging stoner comedy, and the later scenes play out in slapstick hard-R action violence with hints of drama. Somehow, all the genre criss-crossing kind of works. Rather than feeling like a movie overstuffed with influences, Landis uses genre-shifts as a means of ducking out of cliché. Just when the movie seems to conform to a predictable genre beat, a new type of movie takes over as a dramatic left turn. Yet, since all the formats he’s dabbling in are familiar, it all kind of slots into place. Viewers might feel off balance, but everything is still recognizably familiar in the moment.

It helps a great deal that Eisenberg and Stewart ended up in the lead roles. Both share a certain stoic deadpan sensibility that helps sell the silliness surrounding them. They play their comedic and dramatic beats with the same stone-eyed commitment and always hit them on the nose, providing grounding forces in a sea of mashup madness. Other supporting players like Grace or John Leguizamo (who pops up as a nutty drug dealer) tend to go a little broader and are stuck in scenes limited to a single tone. It’s a weird balance, with two sincere performances standing out in a sea of cartoonish exaggeration. I’m tempted to think that the script worked best as a writing exercise that was impossible to bring to life in the same way. Or perhaps director Nima Nourizadeh just wasn’t quite up to the task.

Nourizadeh’s only previous feature is ‘Project X‘, a Found-Footage party flick that valued high-pitched vulgarity above all else. The filmmaker clearly feels that dark toned visuals and filthy laughs combine to form something impossibly cool and sticks to that aesthetic here. There are times when Eisenberg and Stewart’s performances (along with Landis’ script) capture something more subtle, but Nourizadeh tends to pitch his tone at Eleven. His camera is always up to something stylish and his action scenes always explode into uncompromising bloody violence. That’s fine when the movie hits peaks that demand that aesthetic, however it limits things elsewhere. It was likely also the director’s choice for all the supporting players to go big, broad and aggressive. (The less said about Bill Pullman here, the better.) As a result, the movie shares the same sense of overkill as ‘Project X’. It’s simply much too much, for better or worse.

That’s not to say that ‘American Ultra’ is an outright failure. That sort of binary dismissal is unfair. It’s a clever flick that features some big laughs and visceral set-pieces. It packs plenty of entertainment value into a tight 95-minute package, but it’s also a bit hit-and-miss. Still, at least it’s a summer movie that tries. There’s ambition behind all the one-liners, explosions and longing romance. It’s the product of people trying to do something interesting with mainstream entertainment, so even if the filmmakers don’t quite fulfill their ambitions, they’ve still delivered a weirdo little genre effort worth experiencing. It likely won’t be remembered by viewers for long, but at least everyone who shoves ‘American Ultra’ in front of their eyeballs will have a good, geeky and greasy time in the moment.