Sharply written and tailor-made to its two marquee stars, “Billions” deals with plenty of weighty issues but proved most enjoyable for an attribute that a lot of premium-cable dramas can tend to forget: Fun. And that set up a finale that made a number of hairpin turns, before rather niftily laying the foundation for a second season.

In its closing moments (and SPOILER ALERT if you haven’t watched), in which a U.S. attorney, Chuck Rhoades (Paul Giamatti), confronted hedge-fund billionaire and season-long quarry Bobby Axelrod (Damian Lewis), the program actually brought to mind the movie “Duplicity,” which also co-starred Giamatti. Granted, in that corporate-espionage tale it was two titans of industry duking it out, but in each case the show involves powerful men, using every resource at their disposal in an effort to gain advantage over the other.

The last couple of hours also took perhaps the show’s most improbable, bordering-on-absurd element – the fact that Chuck’s wife, Wendy (Maggie Siff), doubled as Axelrod’s in-house shrink was caught directly between them – and made it sizzle, first in Chuck’s betrayal by prying into her computer, and then by Axelrod’s threat to expose intimate personal details of her life. Those events drove a wedge between Wendy and both men, forcing them to tacitly admit the unorthodox triangle in which they were involved.

Mostly, though, “Billions” crackled on the strength of clever dialogue — the finale was written by Brian Koppelman and David Levien, and directed by Michael Cuesta — and those assembled to deliver it. That level of quality that extended to even smallish roles, like Axelrod’s shadowy fixer (Terry Kinney) and oily attorney (Glenn Fleshler). The quotable lines ranged from those of the throwaway variety (“It’s Chinatown, Jake”) to Axelrod’s hilarious barb when Rhoades entered his offices, “I thought your kind could only come in when invited.”

As for Lewis, he played his master of the universe with an almost evangelical zeal, a latter-day Elmer Gantry preaching on behalf of capitalism, all those silly rules be damned. The fact that a character able to realize practically every whim is also a devoted family man – adoring his wife, spoiling his kids, and previously rejecting an opportunity to stray – is only one of the fascinating contractions that surrounds him.

Axelrod could be a wonderful friend – running his business like a frat house with an unlimited expense account – and a terrible enemy. “We are friends for life, or you don’t exist to me,” Axelrod warned during a negotiation, and the threat carried enough menace that it would be easy to see almost anybody knuckling under.

Nor was there any doubt, as the finale again made clear, that Axelrod knew how shady his transactions were, ready as he was to uproot his wife (Malin Akerman) and kids and flee to Europe at a moment’s notice.

In the closing sequence, all that was brought home, promising an even more brutal battle to come, one in which almost everyone else – employees, reporters, charitable foundations – will be treated like pawns in a massive chess game. And if the animus between the two flared throughout the season, it became deeply personal at the end.

“Billions” is hardly the first movie or TV series to cast a jaundiced eye on big business and/or its big-government regulation, but it has managed to weave them together in a manner that doesn’t get bogged down in the details or choke on its own murk, a la “Ray Donovan.” (Having New York Times business columnist Andrew Ross Sorkin among the producers offered the promise of financial savvy, but not necessarily that lighter touch.)

Granted, this isn’t the kind of show that’s going to move markets for a pay network, in the way something like “Game of Thrones” can. Yet in chronicling contemporary gamesmanship involving a certain brand of royalty, “Billions” has, both creatively and practically, yielded a pretty nice and consistent return on investment.