‘Billions’ ‘had to change.’ How (and why) the series blew up its central relationship

Batman versus Superman.

King Kong versus Godzilla.

Rocky Balboa versus Drago.

Rhoades versus Axelrod.

The rumble between U.S. Atty. Chuck Rhoades and billionaire hedge fund king Bobby “Axe” Axelrod on “Billions” is not quite as colossal as those other showdowns, but it has been equally volcanic. The two have been at each other’s throats since the financial drama debuted in 2016, their blood feud at the core of the Showtime series.

Raising the stakes was their attachment to the same woman — Rhoades’ (now former) wife, Wendy, the executive therapist at Axe Capital.

But “Billions” will be shifting gears when it returns Jan. 23 for its sixth season. Axelrod (Damian Lewis) has left the scene, and Rhoades (Paul Giamatti) will be taking on new battles.

The change was prompted by Lewis’ departure. The actor, who also starred in Showtime’s “Homeland,” left “Billions” at the end of last season, fulfilling his long-standing plan to spend more time with his family in England. His wife, actress Helen McCrory, died of cancer in April.

Axelrod‘s absence has forced the series to reset while maintaining its primary focus: The conflict between capitalism and regulation. Despite the differences, though, executive producers say the spirit of the show — and its cutthroat dynamics — are still very much in play.

“It is set in the same world,” said Brian Koppelman, who created the show with David Levien and financial journalist Andrew Ross Sorkin. “But as the world changes, the show has changed too.”

The conclusion of Season 5 saw Axelrod cornered by Rhoades with no way out. Rather than surrender, he fled to Switzerland with the aid of his rival, billionaire Mike Prince (Corey Stoll). Prince, who is just as driven but less brash than Axe, subsequently took over Axe Capital, forcing his predecessor’s devoted staff to worry about their future under a new and decidedly different leader.

Paul Giamatti, left, with Corey Stoll in “Billions.”

(Jeff Neumann / Showtime)

“What is happening is part of an evolution which started when we were examining a certain kind of billionaire,” Koppelman said. “We wanted to see if there can be such a thing as a billionaire who isn’t a drain on society. Is it possible to be a beneficent figure in that position?”

Levien added, “When we started the show, we were very much captivated by silent hedge fund guys trading stocks, trying to stay in the shadows and not become famous. Over the years, we’ve seen people use their prominence and their wealth in the public space to try and move discourse and use that as an extra source of power.”

With Axelrod out of reach, a frustrated Rhoades, who feels that all billionaires are intrinsically corrupt, sets his sights on Prince as his new target.

“Chuck Rhoades sees something that offended him and felt betrayed in a certain way,” Levien said. “Mike Prince sees somebody in his way. So we’re already at a place where it’s personal by nature — they’re two alphas going for the same patch of turf.”

For fans wondering whether “Billions” will be able to maintain its momentum without Lewis, who played Axelrod with an aggressive, sharp edge that was also compelling and charismatic, Koppelman pointed to another popular show that lost one of its original stars after just two seasons: “NYPD Blue.”

“I thought I would never watch ‘NYPD Blue’ again after David Caruso left,” he said. “But then Jimmy Smits came on, and he was magnetic and beautiful in a totally different way.”

In a phone interview, Giamatti noted the key differences between the two billionaires facing off against Rhoades. “With Mike Prince, it’s less visceral and more cerebral than it was with Axe. Mike is more enigmatic than Axe.”

As for his approach to working with Stoll as opposed to Lewis, “It’s less jarring than you would think,” Giamatti said. “Plus, we did that story for five years. ... It feels more Machiavelli than Mussolini, always punching each other and circling each other. It’s kind of like it had to change, in some ways.”

Maggie Siff in “Billions.”

(Jeff Neumann / Showtime)

Stoll, who has had starring and featured roles in multiple projects, including Netflix’s “House of Cards,” FX’s “The Strain” and the recent remake of “West Side Story,” said it was a unique challenge to go from recurring character to series lead.

“I’ve never had the experience of coming into an already established show as the antagonist, someone who comes in to stir things up and create obstacles,” he said. “Being Mike Prince between Season 5 and Season 6 was more different than I expected it to be.

“Mike Prince has a different arsenal of weapons than Axe. He is more aikido than kung fu. But he is as confident a character [as] I’ve ever played. He is so confident that he realizes he doesn’t have to be in conflict to achieve his goals. He disarms them. In this cutthroat, zero-sum game of high finance, people are used to being yelled and cursed at. Mike saves that for when it really counts, when he really needs it.”

Another key character facing dramatic change is Wendy Rhoades (Maggie Siff). At the conclusion of last season, she and Axelrod finally expressed the deep love they had for each other while realizing they couldn’t be together. This season finds her grappling with being cut off from the two most important men in her life.

“Wendy has been complicit in creating her own heartbreak,” said executive producer Beth Schacter. “She is sitting with this mess that she created, and Maggie is so fantastic given this rich material.”

With “Billions” embarking on a new chapter, the executive producers say they feel they can continue the series for several more seasons.

“We’re still really engaged,” said Koppelman. “We love the way the season ends, and we feel it gives us plenty of runway moving forward.”