Former mixed martial arts champion Gina Carano stars in Steven Soderbergh’s “Haywire” as an ex-marine turned contract killer whose life is on the line when her boss, also her former lover, turns on her. While the script often fails to deliver, in a world where ever-shrinking starlets no longer look capable of throwing a convincing punch, it is both refreshing and admirable to see an actress like Carano doing all her own stunts and fighting her way through such an A-list cast.

We first meet Mallory (Carano), who bears an uncanny resemblance to a beefed up version of Minka Kelly, as she’s on the run from both the authorities and her two-timing boss, Kenneth (Ewan McGregor). After leaving former colleague Aaron (Channing Tatum) beaten and bruised on a diner floor, Mallory makes a quick getaway in a bystander’s car, and over the course of the drive relates the events leading up to the present.

One week earlier, Mallory was in Barcelona, allegedly to rescue a hostage. With the mission narrowly completed, she returns home only to be immediately dispatched again by Kenneth. He makes the job sound too easy–posing as the wife of freelance hit man Paul (Michael Fassbender), yet her faux husband has ulterior motives. Mallory manages to escape alive, but this sudden turn of events calls all of her professional relationships into question, causing her to embark on a journey hell-bent on retribution.

The film throws you into the fray with little explanation, but any confusion regarding the story falls to the wayside when Mallory springs into action. Carano is more than convincing as an action star because there are no illusions; she actually did what her character does. Unlike the Lara Crofts and Cataleya Restrepos of franchises past, Mallory needs no weapons. She can legitimately beat the crap out of anyone through sheer force and skill, and it is quite a sight to behold.

Unfortunately, Soderbergh lets the inertia drag on too long between action sequences, which is when the façade slips and Carano’s non-acting background becomes obvious. Although to be fair, she is not given much substance to work with. The writing is weak and poorly scripted around Carano’s physical capabilities, which is a shame because the premise–a woman who can kick ass and doesn’t need to be subordinate to the male protagonist–has a ton of potential.

While a lack of character depth is practically a convention of the genre, in this case, it is as though there is not enough action to fill in the story’s gaps. Soderbergh seems to have tried to go for realism, which is admirable as far as action flicks go, but in between the fight scenes, things simply fall apart and the audience’s interest wanes. Without the dreaminess of “Drive” nor the kitschiness of “Kill Bill,” “Haywire” is merely caught in the middle ground of being different but not distinguishing.