They’re Long Islanders by birth and — they say — by disposition, too. They’re also a team that began some 35 years ago here, when they were a couple of 16-year-olds who absorbed the world around them and ultimately the admonition of writers everywhere: Write what you know.

What New Yorkers Brian Koppelman, 50, of Roslyn Harbor, and David Levien, 49, of Great Neck, know so well is that “greed” is good. It’s a good device for storytelling, and a better one to unlock hearts, where motives are hidden and dreams just a stop on the road to the next big score.

As showrunners of Showtime’s “Billions” — about ruthless hedge fund titan Bobby Axelrod (Damian Lewis) and his nemesis, federal prosecutor Chuck Rhoades (Paul Giamatti) — Koppelman and Levien have found greed is especially good for an ongoing TV show. Based on a concept by New York Times financial reporter Andrew Ross Sorkin, “Billions” now stands as TV’s best series about the almighty dollar. To paraphrase that memorable Hunter S. Thompson line, it’s a long plastic hallway where Axelrod runs free, and good men like Rhoades loses his wife and maybe a career. It’s a cautionary portrait, but also bleakly dog-eat-dog Darwinian, whereby the corrupt are rewarded, and suckers never get an even break.

How did a couple of nice guys from Long Island end up writing so well about a world like this? Practice, mostly. In the late ’90s, Koppelman and Levien co-wrote their first feature, “Rounders,” about a pair of card sharks, starring Matt Damon and Edward Norton. That was followed by “Knockaround Guys” and “Runaway Jury,” then the third installment of Steven Soderbergh’s heist franchise — the so-called “Ocean’s” trilogy — “Ocean’s Thirteen.” They later reunited with Soderbergh for “The Girlfriend Experience.” Levien has also written the long-running Frank Behr detective novel series in the intervening years. Straight out of college, Koppelman explored a career in music — he’s son of former top music industry producer Charles Koppelman, who signed Billy Joel to CBS.

Levien and Koppelman spoke to Newsday about their long-running collaboration. An edited transcript of our chat:

Q: Both of you have long proclaimed your Long Island roots — unusual in that some producers leave for points west and never look back. Why your strong allegiance?

Koppelman: Long Island is baked into us. No matter how hard we try to shake it, it’s baked into us.

Q: The second season premiere opens and closes with a memorable scene at the Empire City track and casino in Yonkers; any similar scenes set on LI this season?

Koppelman: We actually looked at the old Roosevelt racetrack, but it’s a parking lot now. This worked because Axe grew up in Yonkers. … John Singleton directed the seventh episode and some of that does take place at Hamptons’ house. We do shoot on Long Island for sure, but often doubling as Westport. Roslyn represents Westport.

Q: As a team, the two of you have specialized in creating a lot of other “Axes,” or powerful wheeler-dealers with highly flexible moral codes. How did you come by that?

Koppelman: Growing up on Long Island, on the North Shore, we would see how people would use their charm, charisma to tell a story about who they were, and we’d watch how they brought this into their story. We’d hang out at the Kensington Kosher Deli in Great Neck and overhear at the next table this kind of high level rhetorical exchange and you’d be drawn into the story and drawn into the version of the world this man was experiencing. We were 15 years old and loved the idea of people who lived by their wits and who defined who they were in the world just by the way they carried themselves. So we started writing about them and reporting about them.

Q: With Axe and other characters you’ve created, you also explore the notion that some people tend to overlook faults of billionaires simply because they are so rich.

Levien: We were fascinated by what made charismatic billionaires, and made them such magnetic figures with such large groups of people, for whom their success was a stand-in for all kinds of other good qualities in peoples’ minds. We were fascinated by why we are drawn to them. This was something we were interested in long before Donald Trump was a candidate, but now the show does take on a slightly different resonance.

Q: How did you both meet?

Levien: We met on a Musiker Teen Tour in 10th grade, where we flew out West and went to national parks and things like that. We met on the airplane, then rode this bus all up and down the American West and we’ve been like brothers ever since.