He topped the charts with 'This Is Country Music,' but it's his latest rock song that makes Brad Paisley one cool dad. The reigning CMA Entertainer of the Year and father of sons Huck, 4, and Jasper, 2, has two tunes on the 'Cars 2' movie soundtrack, one of which is a duet with British pop superstar Robbie Williams.

"My friend John Lasseter, who directed the movie and runs Pixar, called me and asked if I'd mind stepping out of my comfort zone and write a song for the movie with Robbie," Brad tells Reuters. "It really was out of my comfort zone, more like Led Zeppelin or the Who, but it was really fun. The theme of the movie encompasses spies, cars, international intrigue and comedy, which is really a 'Collision of Worlds,' so that's what we called the song."

"It's an international kind of song that's inspired very much by the film -- it wouldn't exist if it weren't for the story," adds Robbie. "Brad turned up with his guitar and a basic understanding of what he wanted the song to sound like. He played me a few chords and we noodled and twiddled our way into forming this song. It's back and forth colloquialisms between two different countries speaking the same language and not understanding each other -- until now."

Walt Disney Records shares exclusively with The Boot this behind-the-scenes video of Brad and Robbie recording 'Collision of Worlds,' along with clips from the movie. Watch it below.

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Brad's other song on the 'Cars 2' soundtrack is 'Nobody's Fool.' "It's inspired by the most heartbreaking scene in the movie," explains the country superstar, who wrote the track. "Mater realizes that everybody thinks he's playing the fool and he becomes sort of enlightened and realizes that he's not playing the fool -- he is one. But Mater realizes he is who he is, and that was inspiring to me."

Brad also had two songs on the original 'Cars' soundtrack, 'Behind the Clouds' and 'Find Yourself.'

'Cars 2' hits theaters nationwide this Friday, June 24. Check here for local listings.

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