If one were to travel back in time to 2004, the year of Emily Blunt’s first minor breakout role in My Summer of Love, and told the world that she would become a premier female action star in 2015, it would be difficult to believe. But thanks to her turn as a shotgun toting farmer in 2012’s Looper and her scene stealing role in last year’s Edge of Tomorrow (and stealing scenes from Tom Cruise is no small feat), this is fast becoming the case. With the release of Sicario, emerging director Denis Villeneuve (he of Prisoners and Enemy fame) has joined in on the fun, this time elevating her from supporting role to bona fide star.

Blunt is Kate Macer, an Arizona FBI agent who specializes in Mexican drug cartel kidnappings. After a particularly harrowing discovery at a cartel-controlled house, she is drafted into a cross-agency task force by the enigmatic and blustery Matt Graver (Josh Brolin) and his equally enigmatic and entirely more dangerous partner Alejandro (Benicio Del Toro). When a recon mission in El Paso is revealed to be an excursion over the border to Juarez, Mexico, her resolve as a by-the-book agent is tested. In spite of protestations from her FBI partner Reggie (Daniel Kaluuya), Kate continues to work with Matt and Alejandro, even as the line of their tactics’ morality and legality continues to blur.

On its face, Sicario seems to be a bit of a departure for Villeneueve, whose recent output has been marked by a predilection for deeply emotional but small scaled character dramas. The emotion is still present in Sicario, but the scale is huge, with a much larger cast and setting that spans both sides of the border. It does not take long, though, for the through line to become clear. Both Prisoners and Enemy were foundationally concerned with the actions of those pushed to their emotional brink. The same is the case here, as Blunt is constantly left in the dark about the true nature of their task force and how far she will be pushed before she breaks.

This approach to storytelling put inordinate faith in the leads in order for it all to work, and in Emily Blunt Villeneuve has a wonderfully poised and confident heroine. Kate Macer is a maelstrom of conflicting emotions, from her desire to do real damage to the cartels to her unerring moral compass to her needs to be seen as an effective agent. Blunt internalizes it all with aplomb, creating a compelling canvas on which to paint all manner of trials by fire. This could be the role that elevates her into awards discussions at year’s end, and it is certainly deserved.

Brolin and Del Toro are tasked with playing different sides of the same coin, each of them angling for a similar goal with markedly different methods. Brolin deflects the hard edge of his character with his singular brand of laid back charm that draws Kate in with promises of results, while Del Toro provides an altogether more sinister edge, choosing to barter for compliance through fear. Their conflicting styles combined with their unwillingness to let Kate in on their true motives injects a palpable sense of chaos and confusion into the proceedings. The script, from first time screenwriter Taylor Sheridan, keeps the audience as much in the dark on these two as Kate is, making the unpredictability of it all a defining trait of the experience. Anyone or anything could be lurking just outside of view, and relaxation is rare until the credits roll.

Returning after previously working with the director on Prisoners is legendary cinematographer Roger Deakins. The muted blues and rain soaked suburbs of his first collaborations have been replaced by the washed out browns of the desert, and Deakins continues to prove time and again that he is among the best in the game. Villeneuve acclimates himself well to the action; the border is an unforgiving place full of automatic weapons and enemies of all shapes and sizes. With Kate Macer as the film’s eyes, the violence seems to explode out of nowhere, with blurs of bodies and muzzle flashes exploding from every angle. The score, from The Theory of Everything composer Johann Johannsson, reinforces this feeling of disorientation, relying on tone over melody and all manner of propulsive, percussive sounds to punctuate the action. When taken as a whole, Sicario becomes an uncannily efficient machine for dread, more so than either Prisoners or Enemy.

The shortcomings of VIlleneuve’s previous work has been boiled away under the oppressive sun of the Arizona/Mexico border. The punishing length of Prisoners and the go-nowhere paranoia of Enemy held those two films back from their strong visuals and fascinating color palettes. But Sicario is streamlined from beginning to end, a taut, tight and cynical morality tale that does not end how anyone would expect it to, similarly depressing but liberatingly thrilling in the way it goes about its business. It is not the first drug cartel border war film nor the last, and it is paramount for films like this to differentiate themselves in terms of quality or perspective or both. Sicario manages to succeed on both metrics, making it a scintillating experience leaving its audience cold, but in the most satisfying way possible.