Back in 2015, American director Robert Eggers scared and impressed audiences with his feature debut The Witch, a slow-burning horror film about a young girl in the 1630s who may or may not be the cause of a series of maleficent incidents. There, suspense was generated mostly by playing with audience expectations. but the subtext was strong too. The film arguably launched the resurgence of a kind of art-house genre film (including Ari Aster’s 2018 Hereditary) billed as “elevated horror,” more of a marketing than a technical term. Four years later, Eggers returns with The Lighthouse, premiering in the Directors’ Fortnight section of the Cannes Film Festival, and the wait turns out to have been worth it.

From witchcraft, Eggers now turns to the myths of life at sea, amid the elements and isolated from land-locked civilization. At the titular early-20th-century lighthouse lives a nameless old sailor (Willem Dafoe), permanently stationed on the hostile rock. For four weeks, he welcomes the young, handsome, and morose Ephraim Winslow (young, handsome, and professionally morose Robert Pattinson) to be his assistant, but never allowing him to take care of the light itself. With his craggy face and bushy beard, Dafoe looks exactly like you would imagine an old sailor might, and his energetically repulsive performance—there are farts galore—borders on cartoonish parody. But as he speaks an authentic dialect—which, as in his previous film, Eggers and his cowriter (brother Max Eggers) researched extensively—his pirate shtick and songs ring weirdly true.

As in The Witch, Eggers leaves plenty of room for rationality and fantasy to coexist. Winslow oscillates between these two realms, resembling a Romantic portrait with his chiseled jaw and long mustache, but nonetheless perturbed by the strangeness of his surroundings. Further blurring the line between fable and reality is Eggers’s strikingly beautiful and inspired filmmaking style—even more inventive and textured than his already impressive debut. Shot on black-and-white film and in a box-shaped aspect ratio, The Lighthouse has the feel of an early cinema reel (a special lens was created to give the images their antique look), an effect that Eggers playfully underlines with a literal establishing shot early on, presenting the two guards posing in the rain and staring straight into the camera. Rather than seeming like directorial flexing, The Lighthouse’s acknowledging its own exquisite artifice is part and parcel of Eggers’s strategy. No less than his audience, the director understands that a horror movie with sailors stuck in a lighthouse is a potentially silly and cliché proposition, and includes moments of self-reflexive honesty—as when Ephraim himself calls his colleague a parody—to gain the upper hand and lead the spectator further and further down the rabbit hole of suspension of disbelief. Eventually, sea legends don’t seem so far-fetched. It is no coincidence that the lighthouse itself is a real building and not a digitized film set, but also that it was built purposefully for the film; at once a genuine, functional edifice and an artificial place, it is convincing yet absurd. Likewise, by having its characters doing difficult physical tasks around the lighthouse, the film’s style emphasizes its actors’ physicality (like few nonaction movies do these days) to better make them feel like flesh-and-blood figures, even inside a fairy tale.

At the lighthouse, Ephraim’s mind is occupied only with the manual chores the sailor assigns him, and with itself; this proves to be a mixed blessing. Life in close quarters leads the young man to reflect and exercise his imagination. Visions, nightmares and/or apparitions begin to occur— and as predictable as they may be in their Moby-Dick–inspired content, they’re still bone-chilling because of how they stem from Ephraim’s own disturbed psyche. Typical male anxieties are exacerbated by the older sailor’s iron rule (ICYMI, a lighthouse is a phallic symbol); vague but troubled memories and a profound loneliness seep out of the young man’s head and are refracted and distorted by his peculiar surroundings. His and our own preconceived ideas and fears about seafaring and what lies beneath the surface of both the water and the lifestyle seem to become self-fulfilling prophecies; with its array of suggestive images, The Lighthouse is a field day for psychoanalysts.

It is this constant push and pull between amused disbelief and visceral anxiety—between seeing the film as a grotesque, stylized fantasy or a terrifying, realistic drama—that makes it both hilarious and creepy. Jean-Paul Sartre wrote of the ‘bad faith’ of the waiter who is just a little too eager to act like his job requires him to, and Dafoe’s masterfully inflated turn has some of this desire to inhabit the archetypes of his part as though hanging on to it for dear life. If Ephraim plays along, the sailor can better lean into his game, and Eggers lets his actors have as much fun as possible with the colorful language of the time and the stereotypes of manliness: When drunken camaraderie briefly turns into eroticism, a fist fight erupts to quickly repress any nonheteronormative feelings. But if the young visitor, consumed by anxiety, can no longer buy into his colleague’s antics, and a rift appears between them,it’s impossible to say which of the two men is losing his mind. The sailor has his myths, but what does Ephraim have to give for his own life to have some order? If the old man is gaslighting his employee, it might be for his own good—or because the old man has already been blinded by the myths of the lighthouse. The triumph of The Lighthouse lies not only in its darkness, but in how it illuminates the fragility and terror of its characters in front of our eyes.