Martin Scorsese’s Silence, adapted from the historical novel by Japanese author Shūsaku Endō, is an arresting, unforgettable experience. It is not entertaining in a traditional sense, although it can be exciting—even funny. Scorsese and his co-screenwriter Jay Cocks aim to challenge their audience, disabusing their idea of what it means to lead, to be spiritual, and to commune with God. They achieve this with complex performances and a filmmaking style that forgoes the flourishes that define most of Scorsese’s work. The filmmaker lets the material speak for itself, so the cumulative effect leaves a gnawing impression.

In the 17th century, the Buddhist Japanese government persecuted Christians, torturing and killing hundreds of thousands of them. Back in Portugal, the Jesuit priests Rodrigues (Andrew Garfield) and Garrpe (Adam Driver) receive word that their mentor, Ferreira (Liam Neeson), renounced his faith after having spent years doing missionary work in Japan. Rodrigues and Garrpe travel to the country, hoping to rescue Ferreira.

Rodrigues and Garrpe cannot find Ferreira right away, yet pockets of Christians remain, so they offer them comfort through prayer, confessions, and meager icons like crosses made of straw. The government catches wind of their activities, and their subsequent interrogations are insidious. Instead of punishing individuals, they opt to punish the group as Rodrigues and Garrpe watch from a distance. This method turns the idea of Jesus’ sacrifice on its head: Instead of a leader dying for his followers’ sins, the followers die to protect their leader. This weighs heavily on the priests, and Silence essentially follows the region’s Grand Inquisitor (Issey Ogata) as he performs protracted psycho-spiritual torture on the interlopers.

Scorsese spent decades trying to adapt Endō’s novel to the screen. His early life and work explain why: He grew up as a pre-Vatican II Catholic—he even considered becoming a priest—and many of his films are about young men whose inner turmoil and violent environment lead to profound moral failure. This is a personal film for Scorsese—he also faced demons early in life—but he has a curiosity about his Japanese characters, too. The East/West clash at the center of the film runs the risk of lazy orientalism, yet the source material is rich enough to sidestep it (Endo was a Japanese Catholic). There are many debates in the film, but Scorsese and Cocks resist the easy urge to have us sympathize with the Jesuits. While the Grand Inquisitor character has an exaggerated manner of speech, for example, his arguments are stronger.

The first stretch of Silence offers a contrast between Rodrigues and Garrpe: The Christians can escape persecution if they apostatize—a symbolic gesture where they “trample” their feet on a picture of Jesus—and while Rodrigues thinks they should trample, Garrpe argues it would betray their faith. The screenplay does not offer much camaraderie between the two priests, who cling to each other out of base need rather than affection. Instead, Silence reveals its true purpose once they separate. In one agonizing sequence after another, Rodrigues bears witness to pointless suffering, using prayer as a crutch to avoid any genuine reckoning. Scorsese uses cleans edits and classical composition to make us feel like observers alongside Rodrigues, so his reactions of helpless anger are all the more intense.

While the austere cinematography and crisp sound design provide a sense of immersion, Scorsese’s true masterstroke in Silence is his casting. All the major characters, including the Japanese ones, are sharply defined, only to have our assumptions erode as the story continues. Tadanobu Asano plays an interpreter for Rodrigues, and his wry sympathy gives way to needling provocation. Yōsuke Kubozuka plays Kichijiro, a pathetic drunk, and his weak constitution is at odds with a profound understanding of Christian theology. Still, the key to Silence is Andrew Garfield’s bizarre, complex performance. There are moments suggesting Rodrigues’ relationship to God is not especially deep. Garfield calls attention to his weak-willed nature and never once apologizes for it. Rodrigues’ frequent voiceover betrays his half-hearted actions; this well-observed hypocrisy is what makes him flawed and irrevocably human.

Silence makes a major departure from the source material, and that is mostly in a long epilogue after the story’s climax. Scorsese tilts his interpretation of Endō’s book in one direction, and yet he obscures Rodrigues’ nature just enough to avoid a neat resolution. No matter the depth or absence of one’s faith, this is a film that tests our biases and stirs our feelings in uncommon, profound ways.

Silence opens Friday at Landmark’s E Street Cinema and Bethesda Row Cinema.