The phrase “first-time director” tends to summon up a very specific picture: a bright-eyed kid, perhaps fresh out of film school or graduating from YouTube, a Hollywood outsider looking for an in. Dan Gilroy is, well, not that kid. Nightcrawler (out Tuesday on Blu-ray and DVD; available now on demand) is his feature directorial debut, but the 55-year-old writer/director has been knocking around the business for nearly a quarter-century now; his first credited screenplay was 1992’s Freejack, where he met his future wife, Nightcrawler co-star Rene Russo. She’s not the only familiar name in Nightcrawler’s credits — you’ll also see two other Gilroys, Dan’s brothers, editor John (Salt, Warrior, Pacific Rim) and producer Tony (himself a two-time nominee, for writing and directing Michael Clayton). I asked Dan how filmmaking became, for him, such a family business.

“Our father is a playwright and an independent filmmaker, so we grew up in a household where this was being done,” he explains. “When we were in our 20s, we all moved to New York, and they became bartenders, and we all had random jobs. Tony and I started writing, Johnny started cutting films, and it just evolved; we each sort of found different levels to work at, as we grew older. I married Rene, and Rene and I are very creatively close. She reads all my scripts and gives me ideas on them. So when I finished the script and I wanted to direct it, I gave it to Tony, and Tony very generously said, ‘I’ll produce it.’ And that got the ball rolling, for people to go, ‘OK, well, if they’re willing to risk their time and energy on you, maybe I am as well.’ So it’s crucial to have that first person raise their hand, and Tony was that person for me. And my brother John is one of the best editors alive, and I think the film speaks for itself.”

Indeed it does. Nightcrawler was one of the surprises of the fall, a sharp, stinging, often disturbing, and frequently funny character study of a… well, “sociopath” seems fair. Lou Bloom (Jake Gyllenhaal) is an insomniac who stumbles into the world of stringer news photography, freelance cameramen who roam the night looking for crime-scene footage to sell to the “if it bleeds, it leads” morning newscasts. Gilroy says he was fascinated by their world before he even knew what story he was going to tell there.

“I became obsessed with it,” he says. “I thought this was a great idea for a backdrop for a film. And I always thought it was going to be a plot-heavy film: maybe a conspiracy, or a Chinatown. I kept trying different variations of that, and it just wasn’t working the way I felt it could work. I kept putting it to the side over a period of years, and then about two and a half years ago, I started taking the hero character, and I imagined what it would be like if I put an antihero in.”

That antihero makes a strong first impression, with an opening scene of unexpected violence that makes clear exactly who he is, and what boundaries he does and does not have. “I wanted to start off with a violent act,” he recalls. “I did not want a character with an arc. I wanted to break as many narrative rules as a could, so there’s no arc, there’s no redemption, there’s no backstory.” In fact, Gilroy dismisses character arcs as “a narrative fallacy. I don’t know anybody who goes through a major life change, like films present, and somehow transforms. I think we’re pretty much fully formed at a certain point in our lives, and we stay that way for better or worse. So I wanted him to do a violent act at the beginning, so that the audience didn’t think, Oh, he was a nice guy who this job made crazy. That was not what the movie was about.”

What makes Lou more than your typical antihero is the astonishing work Gyllenhaal does in the lead role — it’s a fabulous turn, not telegraphed, but filled with slight indications (a look or laugh held just a beat too long; a motivational phrase spouted with not quite enough sincerity) that something’s way off here.

“He’s fearless,” the director says of his star. “He’s willing to take risks, and I think risks are vital for really any kind of art. So our process was very much one of us saying, I have an idea, and other one, rather than saying My first thought is no… it was, That’s interesting, let’s see if we can try that.” The process appealed to a specific element of Gilroy’s personality: “I gamble. I like the feeling of gambling, and I like to take risks. So I bonded with Jake on that level. Jake came to me and said, You know, I’m thinking of losing weight. Well, 27 pounds later, there’s Jake. It all makes sense now, but that was a big, frightening decision on many levels… to have the chance to work with an actor who is that committed, and that creative, it was just an incredible experience for me. I’m so thankful that I got the chance to work with him, and that he took risks working with a first-time director like me.”

Nightcrawler marks Gilroy’s first time in the director’s chair; it’s also his first Academy Award nomination, for Best Original Screenplay. The Oscars are, of course, an enjoyable spectator sport for those of us who aren’t in the industry, but what does the nomination (and possible win) mean for Gilroy, a working writer/director, on a practical level? “Everybody’s practical levels are different,” he says. “For me, the thing that I want to do next is to write another screenplay, and get another film made, probably independently. So on a practical level, I got most of what I wanted prior to the nomination, in the sense that we got a critical response which was very positive, and commercially we did well, to the point that people will go, What do you want to do next? I got that, which is fantastic.

“The nomination to me goes beyond practicality. It’s just an acknowledgement from your peers, from people you work with, that they appreciate your work. One of the best parts of the whole thing has been going to Q&As and panels, and just meeting people whose work I’ve watched for years, and I had never gotten a chance to meet any of them. Richard Linklater, I’ve become sort of friends with him, and Damien Chazelle. There are very creative, wonderful people to talk to, and that to me has been the benefit from all of this.”