So how does he maintain the physical demands of these beefy roles at age 49? "I work out less and enjoy it more these days," he says. "It's a time in my week where I don't have to juggle things. I can just exercise and be present. When I play Dominic in Fast, I want to look strong but authentic, not buff. But to play Xander in xXx, I work with MMA fighters. And I did a lot of yoga when I played Riddick. There aren't a ton of constants, maybe just cardio work and a lot of core."

Vin Diesel leads the cast in XXX: The Return Of Xander CageVin Diesel leads the cast in XXX: The Return Of Xander Cage

It's been 15 years since he last played Xander, and Diesel feels that the time is right for his return. "I think there's a need to revisit this hero archetype," he says. "He is in some ways the reluctant hero, in some ways the antihero, but his individuality shines."

Diesel also had a personal reason for making such a light-hearted action movie after the death of his friend and colleague Paul Walker. "I needed to play a very happy character," he says, "a character that could smile, a character who could laugh and tell jokes and do things purely for the thrill."

More: Vin Diesel Needed To Play A Character That Could Smile Following Furious 7

For this reboot, Diesel decided to turn the loner Xander into a team player, recruiting costars from India, China, Thailand, Bulgaria, Australia and Scotland (namely Deepika Padukone, Donnie Yen, Tony Jaa, Nina Dobrev, Ruby Rose and Rory McCann, respectively). "Although we come from all over the world, when you see us together you see harmony," he says. "Yeah, they are greater than the sum of their parts! That's what is cool about this movie, seeing this group of misfits come together and work together. It's the love of a lifestyle that brings them together, so they wouldn't necessarily worry about being heroic. What's interesting is that gives them room to grow as characters. You want to think about how they play in this movie, but also in subsequent chapters."

Yes, he's definitely up for further adventures, but wants audiences to enjoy this one first. "I just want them to have fun because that's what this film is about," Diesel says. "That's what you're going to hear. People are going to say, 'Go see xXx because you are just gonna have fun.'"

Watch the trailer for XXX: