Prepare yourself for the most tension-filled take on cartel violence and the War on Drugs

Credit: Richard Foreman Jr./©Lionsgate/courtesy Everett Collection

In Spanish, "sicario" means "hitman." In film terms, Sicario is sensational, the most gripping and tension-packed spin through America's covert War on Drugs since Steven Soderbergh's Traffic 15 years ago. French-Canadian director Denis Villeneuve (Prisoners, Incendies), working from a dense, devastating script by Sons of Anarchy actor Taylor Sheridan, is out to shatter your nerves. And does he ever.

Warning: Hang on in the early stages while you suss out intrigues that rival Game of Thrones. The audience surrogate is definitely FBI field agent Kate Macer, played by Emily Blunt in a powerhouse performance that ranks with the year's best. Blunt proved she could kick ass in Edge of Tomorrow, in which co-star Tom Cruise looked like a wuss by comparison. In Sicario, Kate is damn near a woman alone.

We first meet her in Arizona, in a hideout run by a Mexican drug cartel, with decomposing corpses stuffed in the walls. Nothing throws Kate till she's basically ordered to volunteer for an agency-merging task force that pits one drug lord (Bernardo Saracino) against another (Julio César Cedillo).

Confused? Just soak it up, which is the advice Kate gets from operations chief Matt Graver (Josh Brolin, smartass and stellar), a laid-back manipulator in sandals who claims to be working a defense contract but has the aura of CIA. His associate Alejandro (Benicio Del Toro) is an ex-Mexican-prosecutor-turned-assassin. Does Alejandro have a personal agenda? Look in his eyes. Del Toro, who won an Oscar for Traffic, is tremendous again here, radiating a smoldering cool that throws the sexually unflappable Kate off her game.

Sicario is a setup for scalding action in a world where right and wrong are no longer absolutes. As Kate tries to stand her moral ground while the ground keeps shifting, Villeneuve stages one gut-wrenching scene after another, set to a jittery, jangling score by Jóhan Jóhannsson. And kudos to cinematographer Roger Deakins: His aerial shots of a white-knuckle border crossing contrast vividly with a breathless chase through drug tunnels, and he achieves visual miracles. Still, it's on Blunt's expressive face that Sicario writes its darkest poetry. Prepare to be haunted for a good long time.