Bobby Axelrod, the hedge-fund billionaire of Showtime’s Billions, is a man who oozes mastery.

Right now Damian Lewis, the man who plays him, does not.

In a London photo studio, for emmy's cover shoot, Lewis is failing triumphantly to get his dog under control. Petra, a four-and-a-half-month-old cockapoo, is not only dismissive of her master (no matter his best-actor Emmy for Showtime's Homeland and the gleaming notices he's received for his latest TV lead), she is impervious to his bidding.

She yaps when she wants to yap, hoovers up a few crumbs from lunch and, at one point, wanders into the shot and takes a nap in the background.

"Bobby Axelrod would have someone to do this for him," Lewis says, fumbling with the anti-bark spray as Petra scuttles off.

Later, Lewis will head off to pick up the kids from school. He's in full family-man mode on this day, talking about the school run ("We once got stuck in traffic beside a billboard with Claire Danes and me. My son looked round and said, 'Dad, there's an enormous poster of you on the wall. What's Homeland?'") and looking after the dog.

Present dad is a role he relishes; it was one reason he had misgivings about going back to the U.S. to make Billions so soon after his stint on Homeland.

"When you have two small children and a wife who's an actress [Helen McCrory], and a very successful one, blocking out that much time is daunting — I'll let you know if I'm still married at the end of it," he quips.

"But in the end, it's about the thing that prevails, and that is wanting to do good work." Billions, the critics and the audience agree, qualifies as good work. Its first season averaged 6.3 million viewers weekly, and audiences grew through the run.

The Showtime series plays like a prizefight, setting up Lewis's Axelrod against Paul Giamatti's U.S. Attorney Chuck Rhoades, and letting them go at it the full 15 rounds.

Convinced that Axe, as he's known, is making his money through insider trading, Rhoades makes it his mission to bring him down. But Axe is the friendly face of hedge-fund management — he pays for the college education of the children of friends who were killed on 9/11; he's a loving dad, a self-made bootstrapper in a cashmere hoodie, a loyal husband to Lara (Malin Akerman). He's the bad guy you might confuse with the good guy.

"His self-belief, his confidence, I think is appealing," Lewis says. "And so is the way in which he epitomizes the rise of the working man. I suppose he fits in some way to the idea of the American dream: that any man can make something of himself. I think that's attractive to people."

In many ways, Axe is a classic premium-cable anti-hero from the Stringer Bell or Tony Soprano school — and roles like that require actors of Lewis's caliber to pull off. When David Nevins, president of Showtime Networks, first laid eyes on the pilot script by Brian Koppelman and David Levien, he thought straight away of his Homeland alum.

"Damian and I felt that he would be so right for this role," Nevins says, "and it was incredibly different from what he did on Homeland [as Sergeant Nick Brody, Lewis played a returning POW suspected of turning on his country], I thought it would be exciting for an audience to see his range, and it would be exciting for Damian to show his range."

But just like Lewis, who was back in England with his family, Nevins was hesitant.

"Believe it or not, it wasn't a huge plus to me to take a guy who'd played such an iconic role on our network so recently. Damian's so identified with American audiences as Brody that a) would people accept him as Axe, even though I thought he'd be amazing? and b) would it seem like a failure of creativity to go back to the same actor?"

Lewis had similar qualms. "I wasn't planning to go back and do a long-running TV show," he says. But Nevins reeled out a lure. Levien explains: "Nevins called him and said, 'I know you're perhaps not ready to come back to American TV yet — but I have something, and I'm not going to show it to you because I don't want to get you conflicted.' And of course that was the way he enticed Damian into reading it."

Lewis read the script, then considered the long view. "As with choosing any job, you try to sniff out what the ambitions are for the piece — if it's going to continue to be thematically interesting, if there's a broader conversation that can emerge from it."

And once the group got together in New York, it turned out there was plenty to talk about. Koppelman and Levien — creator-executive producers of the show along with financial journalist and author Andrew Ross Sorkin — had long been fascinated by the new breed of "hedgie": the billionaires under 45, in their casual threads, who call their own shots, fly in their own planes and have the world at their feet,

"There are people who are like nation-states and kings walking among us," Koppelman says. "Hedge-fund titans — and some United States attorneys — had characteristics of both. We spent time researching these worlds and realized that if we could put them on a collision course, we might have something engaging and interesting and important.

Their script spoke to the times, too. "We live in a culture where the sense of what's fair, what's not fair, and the enormous imbalances in access to wealth and power are very much in the Zeitgeist," Nevins observes. "This show can really explore that."

Once he'd agreed to the role, Lewis set about talking to the Bobby Axelrods of this world, the young plenipotentiaries.

"I think they're misunderstood," he reports, "Even though people might understand a little bit about what happened during the subprime mortgage crisis, I think very few understand the distinction between the CEOs on Wall Street and the hedge-fund billionaires operating separately in Connecticut or wherever. So, for me to sit down with them was an opportunity to examine them, to see if there are any behavioral common ground between them."

He also had questions about why they do what they do.

"I wanted to hear a defense, given that they know that what they do is disliked. I sat down with one guy who teaches at a university, and he believes in hedge funds as being market regulators — they're like market detectives, They single out overvalued, underperforming companies, and they have a duty of care to do that.

"Yes, of course, they hope to make some money on the bet that this company is going to fail. And yes, there has been adverse press suggesting that they then manipulate the markets and the press — to convince shareholders to withdraw their money to drop the share price, so they can then make their money.

"All of that might be true in some instances. But if it's clean and people are behaving honorably and honestly, then there is also a compelling argument — that they are there, if you like, to crusade on behalf of the shareholders."

Lewis's father, Watcyn Lewis, now retired, was a broker in the City (London's equivalent of Wall Street); his older brother, William, is chairman of the asset management firm CDAM and previously worked on the equity sales desk at Merrill Lynch. So, Lewis knows the financial world. Even so, does he really buy that argument? His reply is a window on how he works:

"I'm predisposed to buying arguments that advocate for hedge funds because I'm playing a hedge-fund manager. And I'm predisposed to wanting to like what it is they do — to believe that it has a purpose and positive outcomes — because I'm playing one. But I'm realistic enough to know that it's a broad church, the world of hedge funds, and some people are probably behaving more honorably than others."

The briiliance of Lewis’s Bobby Axelrod is that even as viewers flip-flop over Axe’s integrity - or lack thereof - they can’t help but root for him...

For the rest of the story, pick up a copy of emmy magazine, on sale May 17.