LONDON — After three decades on screen and more than 50 feature films, Kevin Bacon has played most every sort of character, from detective to death-row inmate, sex offender to mad scientist.

Now he can add another job to his résumé: supervillain.

In “X-Men: First Class,” Bacon does debonair as Sebastian Shaw, a playboy billionaire bent on world domination. (Aren’t they always?) He’s also a mutant, which pits him against Professor X (James McAvoy) and his new team of superpowered teenagers.

Speaking to reporters in advance of the movie’s opening today, the 52-year-old actor oozed an almost preternatural calm and attitude of humility. If Bacon really were a mutant, his gift might be his staying power.

The role may seem like an odd choice for a guy who has gravitated toward more serious fare such as “The Woodsman” and “Frost/Nixon” in recent years, but Bacon said it was “a no-brainer” for him to join the X-Men rogues gallery.

“Like anything in my career, I don’t like to get stuck in any one sort of thing,” he said. “I feel lucky that the [parts] that come my way are sometimes heroes and sometimes villains.”

Though he joked that “First Class” might not help him land more hero parts, he said he had no qualms about playing the bad guy. As co-star McAvoy pointed out, it’s often the villain who sets the tone of a comic-book movie.

“All of the other X-Men movies have Professor X as the leader of the good guys and Magneto as the bad guy,” McAvoy said. “Most super hero movies need a new bad guy every single movie. Your bad guy defines what your film is about.”

The fifth film in the X-Men franchise, “First Class” serves as a sort of reboot for the series, jumping the action back to 1962 and showing how a young Professor X and his eventual nemesis Magneto (Michael Fassbender) worked together to diffuse the Cuban Missile Crisis.

Bacon explained that his biggest lesson of “First Class” involved working on a film that was so effects-driven, finding focus when surrounded by a fleet of puppeteers and green-screen gadgets.

“It gave me a real appreciation of those actors who walk away from movies like this having delivered a great performance,” he said, mentioning Christian Bale (“The Dark Knight”) and Robert Downey Jr. (“Iron Man”). “There’s a lot of stuff that can get in the way of what you’re trying to do.”

“First Class” was filmed primarily in Britain, but the crew also spent a few weeks in Georgia, where the beaches of Jekyll Island substituted for Cuba. Bacon said that although he enjoyed his stay in South, the timing was terrible.

“Everyone had this idea that we were going to get out of dreary London and go down and shoot this sequence on a nice warm beach,” he said. “Unfortunately, it was freezing. It was front-page New York Times, this unprecedented cold snap in Georgia.”

While Sebastian Shaw is a jet-setting billionaire who inhabits a James Bond-inspired world of swinging ’60s nightclubs and nuclear submarines, the actor said he’s careful to maintain “a fairly simple life.” He and wife Kyra Sedgwick live in New York City, “not in some gated community,” he said. He still takes the subway to work.

“This movie is an exception, but the people that I’m asked to play are usually regular people. They’re cops or they’re in the military or they’re cowboys or whatever. It’s been important for me to stay in touch, stay in contact with humanity.”

And, for the record, Bacon said he has no interest in retiring from show business anytime soon.

“There’s no part of me that has any kind of notion of, ‘I can’t wait to put enough money away so I don’t have to do this anymore.’ I feel very grateful that I’ve been able to make a living being an actor.”