So you play Spencer, a spy, in your new action rom-com Killers. What drew you to the character?

I just thought that it would be a lot of fun to play somebody who was living a [double] life and is secretly capable of doing so much but nobody really knew it.

Did you have any Bond–style spy fantasies while you were growing up?

Yeah, I think every guy has that! [I grew up] with video games and playing 007 on my Nintendo until I beat every single level. I figure that every guy has a little bit of a fantasy of being [someone who] is fully capable of handling himself [no matter what situation].

And it was actually fun just preparing for the movie and learning how to do all of this martial arts stuff. When I was a kid I always wanted to take martial arts and learn how to fight and I got to do a lot of it for the movie.

Did you do your own stunts?

I did all my own stunts except for jumping through glass, which they wouldn’t let me do. Everything that the insurance people would let me do, I did.

Any dramatic mishaps during filming?

Well, I punctured my eardrum on the last day of shooting because I was diving off a boat into the water.

What was it like working opposite Katherine Heigl?

Katherine is an unbelievable chameleon. She’s like one person in her real life and then as soon as [the camera starts rolling], she just immediately transitions into character. I’m convinced she could play absolutely anything.

The director of this movie is an Australian. Have you have much experience with us Aussies before?

I have an Australian that runs my film department - it’s my company - and I’ve been down there twice now and I can’t wait to come back again. And I’m kind of friendly with Rove McManus, I did his show a couple times and we’ve hung out a couple times in Los Angeles.

You’ve obviously got a gift for comedy – were you always the funny one growing up?

Nah, I always wanted to be the funny one but I never really was. I always wanted to be like the ‘class clown’ guy, but I always just got in trouble. I remember being in school and there was like a rabbit outside the window and I threw a pencil at it, and then I had to climb out the window to get it and then I got put on detention! 

And now you’ve got people writing it for you so you know you won’t get busted!

Yeah, now I have people rewarding me for doing silly things.

You also produced this film and you’ve done a lot of other behind-the-scenes roles as well. What’s satisfying about that?

I think there’s a little bit more creative control and I actually just find it fascinating. I love sitting in on editing day and working on a project. Being an actor, where you just shoot something and then it’s over, when they say ‘wrap’ you’re basically done until you go to promote the movie, and then you end up promoting a version of a film that somebody else created.

I like being a part of the process all along the way, so that it’s not just like, ‘Oh okay, now go promote this thing that everybody else put together based on what you’ve done’. It’d be like an artist doing a painting and then giving it away for people to cut it up, chop it up, and turn it into something else, and then being asked to come in and promote it after that’s been done.

Yeah, where you don’t know what happened in steps two to 20…

Yeah, and sometimes you don’t agree with what happened on steps two to 20. Being able to be involved with it all along the way sort of allows you to stay onboard with the decision, so that when you have to go promote it, you’re promoting something that is inclusive of your decision.

You also do a lot of charity work. Is there anything in particular you think our readers should be more aware of?

The one thing that I’m really working on right now is human trafficking. I don’t think people are aware that the average age of entry into prostitution is 12 to 13 years old, and I don’t think that you can leave it to 12 to 13 year olds to make a choice as to whether or not that’s something they want to do with their life.

And so I’m trying to raise awareness about that and get people to start recognising that it is a crime to humanity and have these girls no longer seen as criminals but rather as victims, and actually start encouraging people to police themselves, their environment, and the people around them and becoming more aware of the issue. It’s a humanitarian crisis that we can do something about just by changing out behaviour.

How do you like to unwind?

(Laughs) I unwind by working! The times I feel like I unwind is when we are successful. I do meditation and I was doing a bit of Bikram yoga for a while, I might have to get back into doing that.

You’re also known for being one of the most popular people on Twitter - does it sort of blow your mind to have that many followers?

Well, I think probably half of them don’t know who I am, I’m pretty sure the other half of them are not online (laughs) and the rest are people that are actually following. So it’s probably a little bit smaller than what people think. And also there’s 24 hours of the day and only half the population are generally awake at any given time – we’re not really talking about that many people. It’s a little less intimidating when you start statistically thinking about it!

Killers is in cinemas from July 29.