The first film grossed $350 million and centred on the American Declaration of Independence. The sequel is all about the American Civil War, who was a traitor to Abraham Lincoln and a book in the possession of all Presidents containing all the secrets throughout American History. Justin Bartha plays Riley Poole, the tech expert sidekick to Nic Cage's historian adventurer. And this time round he even gets to drive a red Ferrari.

RT caught up with Bartha to find out more.

National Treasure: Book of Secrets; not so much a movie more an American history lesson.

Justin Bartha: No! It's a movie, a fun action adventure movie. It's not a historical lesson or anything like that; it's just meant to be a fun time!

Well you certainly seem to have a fun time. There's a major scene with a lot of water and that's quite some cast you are nearly drowning with.

JB: I know if you're going to be in thousands of gallons of water then you might as well be with Helen Mirren, Nic Cage, Diane Kruger, Ed Harris and Jon Voight.

Is it possible to be having fun while up to your neck in water?

JB: Absolutely, I have fun every day of my life, and there's nothing I enjoy more than working and acting.

I detect that the glass is always half full for you...

JB: No I wish it were! Just like anyone, I have my days and my other days...

How do you view being the wise cracking geek Robin to Nic Cage's Batman?

JB: [laughs] Well I don't really see Riley like that. People say he's a geek, but I think everyone in the movie is a geek and that's one of the interesting things about the movie; all of these action/adventure characters are intelligent people, using their brains to solve these mysteries. I don't think Riley is anymore geeky than Ben (Cage) or Abigail (Diane Kruger) or any of us, he's a real guy.

And as for the sidekick part, he's more of a Watson to Nic's Sherlock Holmes and wants to be taken seriously like Holmes, and that's his journey in the second movie, to have people like you stop calling him a sidekick!

Fair enough. Did the success of the first film surprise you?

JB: A little bit. You never really know what's going to work. But we had a great pedigree going into it with Jerry Bruckheimer and John [Turtletaub], but what really surprised me was the level of success. People would come up and say it was their favourite movie and that it was their family's favourite; I knew people liked it but didn't realise they loved it so much.



Sorry to harp on, but audiences will discover little nuggets of American history...

JB: Well, there's something extra for you. You have fun and you leave the theatre and maybe your kids are more interested in learning stuff.

The film is all about lateral thinking and puzzles, are you any good at that stuff?

JB: No actually I'm not at all; I have no patience for those kinds of things.

So the moment in the film, surrounding page 47, is that going to be the focus of the next film?

JB: If I told you that I would have to kill you.

Does the Book of Secrets really exist?

JB: If I told you that I would have to kill you. It's a secret if I told you it wouldn't be a secret anymore.

The next film for you is Shoe at your Foot; tell us about that.

JB: It's a romance shot in Paris, I play a guy who falls in love with a French girl...

Any red Ferraris in that?

JB: [laughs] Sadly no Ferraris of any colour!