The title of Denis Villeneuve’s new film originates from the time and geography of Jesus. “Sicario” — a translation of the Latin word sicarii — refers to an offshoot of Jewish Zealots who fought a (usually) stealth war against the occupying Romans. The sicarii (literally “dagger-wielders”) were known for concealing small knives in their clothing and using them to discreetly attack Roman sympathizers in crowded areas. Responding to Roman violence and oppression, the sicarii provided their own measure of bloodshed.

Keeping with the spirit of this original definition, the movie’s opening text tells us that “sicario” now means “hitman” in modern-day Mexico.

Villeneuve uses “sicario” here as a metaphor for both the war on drugs and the struggle to understand violence in the midst of oppression. While Villeneuve’s analogy certainly pertains to the cartels, the United States government also embodies the sicarii spirit. Chaos has become their mission, violence their retaliation. Sicario presents an environment where the line between good and evil is nearly indistinguishable in the jagged, morally ambiguous wasteland of the United States/Mexico border.

In this way, Sicario is one of the best, most thrilling films of the year, not simply for its bottomless well of intensity and tone, but because Villeneuve also creates a world that’s thematically rich, dark, and familiar.

As with the best filmmakers, Villeneuve refuses to give us all the answers.

Sicario begins with an FBI raid on a cartel hideout in Arizona. Led by agent Kate Macer (Emily Blunt), the team finds the hostages they were sent to locate: their bodies are decomposing behind the walls of a newly sheetrock-ed building. The images cause our stomachs to churn and the agents too lose their lunch.

After the failed bust, Macer is recruited by a flip-flop wearing government agent named Matt (played with dark wit by Josh Brolin). Macer agrees to join Matt in tracking down a prominent drug lord, though she’s unsure of both who Brolin’s character works for and their mission’s details. Matt’s an awfully generic name and his loose, vague responses to her questions don’t reveal much. As the group makes an excursion into Juárez, Mexico, it’s not long before Macer realizes she’s only along for the ride. In fact, that’s all Macer’s character does the entire movie, even as the team continues their search for the notorious cartel leader. Blunt’s posture stands brilliantly heroic in the film’s advertising, but her character is anything but an action star. Though Macer’s character never wallows in one-dimensionality, it’s obvious she’s a lamb among wolves.

Sidelining your principal character, and the main focus of the film’s marketing, is a gutsy call by Villeneuve. Consequently, Sicario’s plot is purposefully disorienting at times; the audience’s knowledge and perspective mirrors Macer’s. There are large stretches of the film where we’re unsure of what’s happening, though that seems to be the point. Macer acts as an observer, a window into America’s war with the drug cartels. Her journey into bleakness mirrors our journey into bleakness. She’s in the dark; both morally and logically.

This all plays into Villeneuve’s endgame. Interacting with all the bloody mess, backhanded deals, and unsanctioned hits, Macer begins to ask herself: “What are we doing here?” We too ask the same question: “What is America doing here?” Are we making a difference in the drug war or simply adding to the problem? During Macer’s first mission with the team, one character tells her, “Nothing will make sense to your American ears.” Macer’s previous perception of the crisis and, frankly, ours, isn’t grounded in reality. It’s idealistic.

Revered cinematographer Roger Deakins (True Grit, No Country for Old Men) reflects this perspective in a splattering of brilliant images scattered throughout Sicario. Numerous shots of sunlight illuminating dust particles in the air reinforce Macer’s mental angst; her virtue exposes the less glamorous aspects of the government’s work along the border. Images of fogged mirrors, lingering haze, and sand displaced by explosions and gunshots highlight the unseen grit and ethical ambiguity sulking through the scenes. A running gag in the film is the smoking habit Macer picks up after joining Matt’s squad. She’s gone from noticing the dust to breathing out the fog herself. Gorgeous aerial shots separating the scenes communicate an unfiltered, though limited, eye — one we have through Macer’s spot on the team. We, like God, view the battle from an alternate ethical perspective.

Speaking of God, there’s not much mention of the supernatural in Sicario, though traces of His presence, like in Villeneuve’s Prisoners, make cameo appearances in the background. Religious icons dot the walls of houses, juxtaposing with the violence and corruption happening around them. If the cross is a symbol of God’s presence, the hanging bodies of slaughtered individuals are the cartel’s pseudo-religious icons. One person tells another, “Time to meet God.” When one inhabits the cross-section of hell and earth, the characters wonder if a supreme and just lawgiver will one day separate the good from the bad.

This ability to distinguish virtue from evil is a trait that Macer (and the audience) doesn’t always have, primarily because some individuals seem to inhabit both at once. Their icons are fused together in a mess of depravity and imago dei, both as a Zealot and a disciple. Macer’s biggest misgivings lie with Alejandro (Benicio del Toro), a Mexican national working with Colombian officials, and now Matt. Del Toro steals the film with his performance, personifying both humanity and brutality. His violent methods get results, but can he be trusted?

As with his previous films, Enemy and the sadly underrated Prisoners, Villeneuve uses artistic strokes to create a rich hue of tone and intensity. Sicario settles like a cloud of weightiness for its entire 120-minute runtime, laying its tentacles into viewers through grisly images and anvil-like force. Sicario isn’t content to insert the knife, it wants to twist it too. The action set pieces act as white paint on clenched knuckles. A sequence on the border between Mexico and Texas stands out as the most riveting. But as powerful as these scenes are, the story takes a back seat to its themes.

As with the best filmmakers, Villeneuve refuses to give us all the answers. Sicario, like del Toro’s character, doesn’t initially fit into one category. Villeneuve lets these ideas settle over us during the film, hang above our heads as we walk out, and attack us in our sleep. Do the ends always justify the means? When do we cross the border, and when do we cross a line? Is a little cloak and dagger chaos ever appropriate?

One cartel leader says to an American official, “We learned this [brutality] from you.” Watching Sicario, one gets the sense that the means employed to stop the cartels — torture, murder, and threats — only escalated the conflict’s inhumanity. A symbolic shot during the film’s third act outlines an American soldier wielding a knife as he prepares for battle. The blade and his figure stand silhouetted against the night sky as he walks into the very stronghold of the cartel. The image recalls the sicarii of old — a knife under the guise of anonymity that slices chaos into being.

While Sicario leaves conclusions up to its viewers, its most riveting scene occurs when a weapon is lowered instead of discharged. The sequence is as mesmeric as it is tantalizing. Sicario won’t let us leave without resting this image on the altar of justice.

In a land full of wolves and Zealots, might there be a lamb who can make a difference?