Now that the opening of Nightcrawler is only a day away, let’s talk about Prince of Persia. Actually, let’s talk around Prince of Persia: Let’s talk about what Prince of Persia meant for its star, Jake Gyllenhaal, the kid-faced charmer who, in his progression through movie stardom, had hit nearly all the requisite notes.

Gyllenhaal burst onto the scene with a sincere, somber performance opposite a seasoned vet, playing Chris Cooper’s son in 1999’s October Sky. Next came the cult classic, Donnie Darko, which makes even less sense than you remember; Gyllenhaal’s presence helped make that character, and film, feel at least tangentially related to human beings. The rest of Gyllenhaal’s filmography, both good and bad, continues to fill in gaps with remarkable efficiency: rom-com (The Good Girl), disaster (The Day After Tomorrow), loud drama (Jarhead), quiet drama (Brokeback Mountain), Great American Cinema (Zodiac). By the end of the 2000s, a blockbuster franchise was all we needed to anoint Gyllenhaal as a legitimate movie star.

Prince of Persia: The Sands of Time made $335 million worldwide, but in the United States, it didn’t crack $100 million. And more damaging than the box office was the deeply absurd image of Gyllenhaal, hair and muscles grown out, sword-dancing around in some Kabuki pantomime halfway between Arabian Nights and Aladdin. Gyllenhaal didn’t look like a prince, of Persia or anywhere else — he looked like a prep-school lacrosse player.

Walt Disney Pictures

Despite the respectable gross, Prince of Persia signaled the end of Gyllenhaal’s bid for mainstream movie stardom, insofar as that kind of thing still exists. It also marked an emancipation from the shackles that come with mainstream success and a subsequent creative awakening, one that culminated in 2014 with a body of work not only as good as any other actor’s this year, but also as weird. Jake Gyllenhaal left the A-list and lost his damn mind. In the best possible way.

Gyllenhaal had shown signs of lunatic potential in the past, of wanting to chase his own interests and eccentricity rather than play the stock hero. Rather than choose a more conventional war film, one in which he could spend 135 minutes grimacing through heroism, Gyllenhaal went with Jarhead, a subversive and bizarre take on America’s conflicts in the Middle East that featured very little actual shooting or violence, and far more of the war that we don’t see on screen very often: the boredom, discomfort, sadness, and masturbation. Jarhead is not a pleasant movie to watch, and Gyllenhaal’s decision to make it points toward a sense of self-indulgence — the good kind, the kind that allows you to make a movie the public might not adore unthinkingly — that hadn’t been there in his work to that point.

Then there’s Zodiac, the superb David Fincher epic about the Zodiac Killer that puts Gyllenhaal in the role of a cartoonist who becomes obsessed with the crimes. Fincher purposely broke Gyllenhaal’s spirit during filming by deleting takes in front of him, or doing nearly 100 takes of a single scene. Despite the bloodletting, or because of it, Gyllenhaal’s performance in the film is excellent. He behaves in a strange, almost animalistic way, flitting around the investigation like an insect; by the end of the film, his deep presence in the story’s events feel satisfyingly at odds with the character’s idiosyncrasies.

It’s those idiosyncrasies, first promised in Zodiac, that characterize Gyllenhaal’s best work. After enthusiastically pushing the boundaries of type in two exceptional genre movies, Duncan Jones’s Source Code and David Ayer’s End of Watch, Gyllenhaal crystallized his approach as Detective Loki in Denis Villeneuve’s Prisoners. In the script for Prisoners released by the studio before Oscar season, Loki is described like this:

DETECTIVE LOKI, 33, sits at a darkened table, finishing up his duck. He’s the only customer. Hair cropped, suit pressed; looks more like a cadet than a detective.

Once Gyllenhaal got to him, Loki had a neck tattoo and a haircut like Johnny Depp’s in Cry Baby, his shirt buttoned all the way up. He also gave the detective an eye twitch, which was his way of visually manifesting the story’s overload of information. If he looked any less like a cadet, he’d be shooting heroin in a Hell’s Kitchen apartment in 1983.

Prisoners didn’t just show Gyllenhaal’s depth as an actor — we’d seen that in Brokeback Mountain, Jarhead, Zodiac, and more. It showed his willingness to get weird.

Gyllenhaal actually shot Enemy — also directed by Villeneuve — before Prisoners. But Enemy wasn’t released until 2014. If Prisoners is Gyllenhaal’s Bringing It All Back Home, Enemy is his Tarantula. That has a double meaning: There are massive, inexplicable arachnids in Enemy, as well as doubles, underground sex clubs, and psychological tremors. The film is based on José Saramago’s novel The Double, rather than Dostoevsky’s, and it shares Saramago’s notion of a world that always succumbs to its strangeness and perversity.

Enemy isn’t just a curiosity. Gyllenhaal plays two roles — an introverted, terrorized college professor, and an actor with a pregnant, beautiful wife. He renders them as id and superego; their existence is never explained, but it becomes obvious that both cannot continue to survive in the same world, and Gyllenhaal shows how their existences tear at each other in different but equally serious ways.

Like Enemy, Nightcrawler, the first directorial effort of screenwriter Dan Gilroy, is a movie that takes a few days to set in. In Nightcrawler, Gyllenhaal plays Louis Bloom, a self-possessed idiot savant who stumbles into the Los Angeles world of nightcrawling, or stringing for TV news stations. At a USC screening of Nightcrawler, Gilroy talked about how he wanted Bloom to be a childlike sociopath, challenging the audience’s ideas about likability and justifiable conduct. And here, Gyllenhaal’s boyishness becomes an asset: As he descends further and further into the vortex of his own behavior, his massive eyes and effortless charisma give the proceedings a sense of plausibility.

Gilroy said Gyllenhaal brought many of the character’s qualities to the film: They agreed that Bloom was a coyote coming out of the California mountains at night, and Gyllenhaal decided that the best way to show his character’s coyote tendencies was to lose 30 pounds. For the duration of filming, Gyllenhaal would run or bike to set, then eat kale when he got there; he’s so skinny in the movie that his face becomes an exercise in chiaroscuro. He also added the character’s signature sunglasses and man bun, which he wields as a sort of defense mechanism.

Nightcrawler is a movie so dark, it takes a while to figure out if it’s horror or black comedy. This is further confused by a tonally inconsistent second act. Until the fantastic finale, which sets straight the film’s tenor and sense of self, Gyllenhaal’s unhinged performance is the main anchor. If it isn’t the best acting of his career thus far — and it might be — it’s certainly the most entertaining. Every time Bloom gives one of his inspirational-speaker PowerPoint spiels, it’s like listening to Steve Buscemi’s rants in Reservoir Dogs, or Kevin Spacey lecture about sin in Se7en.

That’s the territory Gyllenhaal is staking out for himself. He’s becoming one of those actors with a fog of war — an actor capable of emotions and maneuvers that you wouldn’t have anticipated. But unlike Spacey and Buscemi, he’s also still pretty, still familiar. Gyllenhaal will never be a movie star. Fortunately, he’s become something better.