Already three films into his directorial career, the boundlessly talented Christopher Nolan still feels like the world’s most precocious adolescent who has just discovered existentialism. “Memento” asked us what it meant to be human by ingeniously playing with the fleeting nature of memory (unfortunately for the protagonist, his memory fled every 20 minutes or so). It seems only natural, then, that his next project would deal with the second-least dependable of human capacities — perception.

His third effort, a remake of the 1997 Norwegian thriller “Insomnia,” displays many of the same stylistic and thematic characteristics of his previous two films and of the neo-noir in general. However, whereas “Following” and “Memento” were plot-driven almost to a fault, “Insomnia” is all about atmosphere, atmosphere, atmosphere.

From the opening shots of a tiny plane drifting over the desolate woodlands of Alaska, it’s more than apparent that the setting (an Arctic town that experiences stretches of perpetual daylight in the summer) will be just as integral to the story as Detective Will Dormer’s (Al Pacino, “The Godfather”) inability to sleep. The film’s not-so-subtleties aren’t shy to admit it either — the town’s name is Nightmute, the “dorm” in “Dormer” is the root for “sleep” in countless other languages, and, uh, the movie’s name is “Insomnia.”

Dormer and his partner-in-the-solving-of-crime, Eckhart (Martin Donovan, “Malcolm X”), are sent to Alaska to investigate the mysterious murder of a high-school girl, an escape which also allows them to lay low during an internal-affairs investigation back home. These plots drift together (on what has to be the foggiest beach in the world) after Dormer mistakenly shoots Eckhart, the silhouette he thought was the suspected murderer.

The incident haunts Dormer, both when he can’t sleep during the “white nights” and when the man he was aiming for turns out to be the only one who saw him do it. The murderer, Walter Finch (a thankfully sedated Robin Williams, “Death to Smoochy”), approaches Dormer with a confession of his own crime and, after having seen Dormer’s, a blackmail threat. Dormer’s sleeplessness continues to cloud his judgment, especially as Finch manipulates and makes him question his own motives.

As the veritable personification of the word “haggard,” Al Pacino lends a nice deal of gravity to a character who futilely attempts to balance right and wrong. He squints and slouches his way to skillfully drawing out Dormer’s moral ambiguities, a task made more taxing as his conscience weighs down on his already weary mind and body.

Williams is effective if for no other reason than that he was cast so heavily against type. He manages to keep from mugging long enough to communicate Finch’s creepiness, and it’s a testament both to Williams’ sporadic bursts of talent and Nolan’s abilities as an actor’s director.

Nolan’s direction is conspicuously inconspicuous — the story is light on action and heavy on backstory, a problem that could’ve been solved by Nolan’s knack for flashbacks and disregard for chronology. The script is rife with expository monologues from Dormer and Finch in the film’s latter third, just as it is supposed to be building to climax.

“Insomnia,” however, again proves Nolan to be a compelling storyteller, even if his name is absent from the writing credits. Certainly, if given another Hollywood budget without the constraints of a remake, Nolan’s next project should be something to lose sleep over.

Grade: AB