Sicario trailer features Emily Blunt, Josh Brolin

In the war against drugs, Sicario‘s FBI agent Kate Macy (Emily Blunt) hopes to make a difference while working along the U.S.-Mexico border. But doing so honestly proves difficult when she teams up with the mysterious Alejandro (Benecio del Toro).

The new trailer for Sicario, directed by Prisoners‘ Denis Villeneuve, probes a little deeper into the murky backgrounds of Alejandro and Josh Brolin’s Matt, who seems perfectly comfortable with a strategy that calls for dramatically overreacting to the drug cartels operating around Juarez. Kate is forced to second-guess what she knew to be true about an operation like this while fighting alongside Alejandro. “Nothing will make sense to your American ears,” he says. “But in the end, you will understand.”

Sicario opens in theaters on Sept. 18. For more on the film, check out EW’s Fall Movie Preview issue

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