Jesse Eisenberg and Kristen Stewart are two performers who have such well-established onscreen personas – thanks to films like The Social Network and the Twilight saga – that it’s hard sometimes not to take that baggage into the theater with you whenever either actor appears in a film. Perhaps it’s fitting then that the duo who shared the screen in 2009 comedy Adventureland are back together in American Ultra, a film which allows each of them to stretch their acting muscles (if only slightly).

From director Nima Nourizadeh (Project X), the action comedy centers on Mike Howell (Eisenberg), a burnout working at a convenience store who spends most of his time getting high with his girlfriend (Stewart). Unbeknownst to him, Mike is actually a government trained weapon of the Jason Bourne variety, a shocking truth that suddenly comes to light during a deadly encounter one night.

Considering that the emotional crux of American Ultra relies on the chemistry between its two leads, the fact that Eisenberg and Stewart absolutely rekindle the same spark they shared in Adventureland bodes well for the film early on. Eisenberg continues his ongoing string of strong performances here, and though he largely riffs on the same neurotic, rickety big-screen persona that audiences have seen in films like Zombieland, that preconception actually underscores the drastic turn his character takes once his combat skills kick into high gear. He may not have the greatest range as an actor, but Eisenberg has proven he’s capable of mining new material out of his niche, a gift that he’ll no doubt return to as Lex Luthor in next year’s Batman V Superman: Dawn of Justice.

Taking one step further away from the shadow of Twilight, Stewart turns in an endearing – if somewhat underdeveloped – performance. As far as audience stigma is concerned, she has an even more difficult task than Eisenberg and mostly succeeds. Meanwhile, the rest of the cast services the script relatively well. Topher Grace gets some choice comedic beats as the sarcastic suited villain, though he never quite escapes cliché. Connie Britton, John Leguizamo and Bill Pullman are all welcome additions as well, but they are severely underutilized, and fans may be surprised how little substance they actually have to work with. The focus of Max Landis’ (Chronicle) script is instead deservedly put on Mike’s newfound skills and the effect this revelation has on the life he’s built for himself.

As stoner comedies go, American Ultra aspires for the same over-the-top lunacy as films like Pineapple Express and Jay and Silent Bob Strike Back. However, the film mistakes ultraviolence for comic excess, demonstrating how badass Mike is but wrapping his antics in what amounts to a rather prosaic plot by the time credits roll. At times, Nourizadeh appears to be channelling the party vibe of his feature debut, but the film doesn’t really develop into the hyper-stylized action thrill ride it clearly hopes to be. Moreover, the film’s stars – and, certainly, its characters – only intermittently take time to revel in the chaos surrounding them, choosing instead to keep the film’s stakes firmly in place. While this keeps the tension up, it creates a bizarre sense of sadism on the part of the filmmakers, who rarely give viewers the chance to chuckle at the absurdity of it all.

Regardless, there’s enough in American Ultra to justify a trip to the theater. Eisenberg, Stewart and the talented supporting cast are all in good form, and the genre mashup of stoner comedy and espionage thriller makes for a fun concoction, even if the two storytelling approaches don’t mesh as well as one might hope. It’s an ambitious film that never completely coalesces, but its effort makes for an intriguing cinematic experience nonetheless.

Rating: 3 out of 5

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