Nightcrawler is a lean, mean, indie-feeling film that purports to show the “sordid underbelly” of television news-footage gathering, and we assume, by extension, the sordid underbelly of, uh, something bigger. While it uses the topic of gathering video footage as its story, what it really gives us is a first-time film by a screenwriter- turned-director of great promise, and a couple of performances worthy of viewing and study.

Plot: Young and strange man is stumbling through life, looking for work and a purpose. He stumbles upon the morally questionable trade of gathering gory and violent video footage for local television stations. He gains a partner, a place in the dark world of “graphic footage,” and a semblance of distorted confidence. He finds a way to get rid of his competition, weasels his way into the personal life of his TV station connection (a fine Rene Russo, fighting against some incredible plot turns that her character is involved in), and faces one moral crisis after another, all of which he fails in spectacular fashion.

The film moves well, and is an impressive first effort by Dan Gilroy, writer of The Bourne Legacy, Real Steel, The Fall and next year’s Stan Lee’s Annihilator. It has the look of a Michael Mann film—all surfaces, colors and slickness. But it’s more than the look. It’s also paced well, with nerve-wracking chase scenes (including the chase after the big story), and suspenseful slower scenes that build into high-tension set pieces. This is a director to keep an eye on.

Ironically, it’s the script that occasionally falters. Russo’s character isn’t always believable in her actions, though this underrated actress does her best to bring life and credibility to every moment. There also seems to be a set-up for things that aren’t picked up later (spoiler alert: the rich man we first thought was dead but wasn’t).

What stands out the most are the performances of the two male leads, with Jake Gyllenhaal deservedly getting the most attention. This is the most intriguing, fascinating, attractively repulsive performance since that of Joaquin Phoenix in The Master. Gyllenhaal’s Louis Bloom is an original, and a kind of acting experiment on JG’s part. Bloom is needy, scary, alternately simplistic and inscrutable, and ultimately unknowable—both because we are never quite given enough information to pin down this character, and also because we really don’t want to.

He calls himself “a fast learner,” and he is. But what he mostly learns is pap from the Internet, business and “life success” clichés that he has clearly taken in and made his own on some shallow level. It’s as if Bloom is working to create his own outward persona and his own personal interior life at the same time, but scouting the web for personal and business success training. And too often for our comfort, he accompanies his regurgitations with a smile that masks and reveals; it masks any depth, and it can reveal a joy in things a normal person wouldn’t find any joy in at all.

JG, who lost 30 pounds for the role, credits the coyote for inspiration, and he certainly moves likes one throughout the film. But wherever he finds his touchstone, this is a brave, inventive performance of a person few of us would ever want to know, but a person we can’t take our eyes off.

Balancing and highlighting the oddness is the utter realism and believability of Riz Ahmed, a British actor virtually unknown on this side of the pond. It doesn’t have the juice of Gyllenhaal’s performance—and it’s not supposed to—but it’s an Oscar-nomination-worthy performance nonetheless. As Rick, Bloom’s “employee,” Ahmed gives us a fully fleshed out portrait of a young man who is desperate for work at first, and then begins to grow in confidence over time. He has a certain internal strength and moral center, and it’s a joy to watch Ahmed react to outside circumstances—especially Bloom’s rapid-fire and almost convincing life platitudes—and eventually connect them to his own sense of right and wrong. Ahmed’s is the performance that grounds the film in realism and helps define Bloom’s character, and allows Gyllenhaal to create an almost otherworldly character that doesn’t float away into the realm of the absurd.

Bill Paxton is in it, and yes, he’s fine, as are all the secondary parts. But it’s JG who will get all the attention, deservedly so, for a unique and unsettling character. But it’s his character’s relationship with Ahmed that defines and reveals his character. Unlike Bloom’s relationship with Russo’s character, which is ultimately just too far-fetched for full credibility, Bloom’s connection with Ahmed is what makes Bloom come out and reveal himself for the grotesque and intriguing creature he seems at the start, and for the even more grotesque and intriguing creature he proves himself to be.