DWAYNE JOHNSON, alias the wrestler known as The Rock, is a handy man to have around in an emergency. If you’ve got a film franchise that needs boosting to improve its performance at the box office, then he’s the man for you.

He’s already done it with Fast & Furious and in Journey 2 Mysterious Island. No wonder he’s earned the nickname “franchise Viagra”.

Now he’s putting lead in GI Joe’s pencil in the second action blockbuster based on the Hasbro characters.

GI Joe: Retaliation is certainly better than the first movie (not difficult) and Johnson, together with a cast that takes in Bruce Willis, Jonathan Pryce and Ray Stevenson, helps deliver an actioner that won’t disappoint fans of that type of thing.

“It’s interesting how it all came into play in terms of the franchises. But it really came down to whether I loved the script and whether I could come in and elevate it a little bit,” says Johnson, who followed both his father and grandfather into the professional wrestling ring, as The Rock, before branching out into movies with The Mummy Returns and The Scorpion King “Trying to elevate GI Joe was very easy because we had a filmmaker (Jon Chu), who was new to the brand. He loved GI Joe, had a great passion and a deep connection to GI Joe, plus you also had the studio in Paramount that does franchises very well with Transformers, Star Trek and GI Joe.

“They realised with GI Joe that there was room to elevate the franchise and make a better movie the second time around. You also had actors involved who all were very passionate about it and loved the mythology of GI Joe. The work was hard but having everybody in that spirit was great.” Johnson is a pretty busy man with movies and a return to wrestling. “I’ve been called the hardest working man in Hollywood – by myself,” he jokes.

“It’s a very busy time and it’s a fun time.

What makes it fun, for me and for audiences, is that it’s a bit like a buffet. So, whatever you want, you come and you’ll get that in terms of them being diverse.

“It’s also a challenging time in the schedule because anytime you have movies coming out, which of course you have to promote, and they’re fairly big movies.

“I’m also preparing for WrestleMania and for Hercules 2 at the same time, so it’s a delicate balance of trying to balance the schedule out with all the press and also with the 12 to 14 week prep for Hercules 2 and, of course, putting boots to asses.”

LAST year, he made a return to the WWE (World Wrestling Entertainment) as host of WrestleMania XXVII. And next month he’ll compete against Jon Cena in WrestleMania XXVIII in Miami.

As for GI Joe – in which he plays Roadblock – he connected to the mythology of the title character and the love people have for it.

“That was why it was really important for us to respect and to really pay homage to the mythology this time around,” he says.

“When I was a kid I was into GI Joe and Star Wars. I was GI Joe and Snake Eyes and I was Han Solo and Bobba Fett.

“For me, I had two cool moments making the film. One was the scene with Bruce Willis, where we’re looking at the tank, and the audience doesn’t see what we’re looking at and Bruce says something to the effect of it not being driven in neutral. And the other cool moment was sharing a scene with Snake Eyes.

“One of the really cool things about the movie, and the franchise, is the duality between the reality of boots-to-the-ground soldiering which transcends every culture that it relates to, but you also have the other side to that, which is the fantastical world of ninjas with Storm Shadow and Snake Eyes, and these amazing sequences in the Himalayas.”

Perhaps he’ll nab a role in the new Star Wars movie. There’s been a lot of chatter about him and that revived franchise, he admits.

“It blossomed out of me saying that I was into GI Joe and Star Wars as a kid. I did this interview where the journalist said, “Hey, you should call JJ Abrams (who’s directing the new Star Wars)’.

“And I said: ‘Yeah, sure, I’ll call him’. And, all of a sudden, I was going to be in the new Star Wars. I would love to do it, sure, but again like the GI Joe franchise, there’s an emotional connection to Star Wars. So, Jedi, Sith... you got it.” He has a long list of hard-fighting characters to his credit, but who’d be the last man standing in a rumble? “My character from Be Cool, Elliott Wilhelm, because he was probably the toughest son of a bitch I’ve ever played, who happened to be gay,” he reckons.

Despite all the weapons Johnson gets to fire, he enjoys using his own muscle power the most. “I do enjoy that. I enjoy being able to drive the world’s fastest tank. It’s a big kick.

I got to fire some pretty massive weapons.

“The fight with Ray Stevenson was pretty challenging because Jon had the idea of creating a fighting style that hadn’t been seen before on film. That’s pretty lofty. So we did this thing where we had two weapons at the same time, where we’re trying to evade the bullets coming at you, but at the same time trying to fire and kick and do our martial arts.

“So, Ray and I were working on that for weeks and weeks and weeks to try and get that down. It’s cool shooting guns and driving tanks, but there’s nothing like good old knuckle sandwiches to the mouth. I enjoy that.”