Inside Justin Bieber's New Believe Concert Tour

Exclusive! Get some fun scoop on what to expect when the hitmaker hits the stage

Justin Bieber is "working his butt off" for his upcoming Believe world tour.

So says his director Jon Chu.

"We're trying to make it fun," Chu told me at the Hit & Run premiere in L.A. "Every time I go too serious, it becomes boring. It's like, 'We've seen that before.' So Justin's at a point where you want the biggest, funnest adventure you can go on. We're playing it like a big Disneyland ride."

Chu revealed there will be a "score playing" when fans walk into the arenas. "There's going to be things that fall on you," he said. "The things where you think they are, aren't really there. We're trying to make it an immersive experience so you never know what to expect."

And that goes for surprise guests. "The hardest thing for me as a director is that people love to join him in difference cities," Chu said. "Every city we go to there's some artist in town who wants to get up on stage and Justin's great like that.

"Literally, it's by the seat of your pants," he continued. "We have things planned, but then you throw in Snoop Dogg, you throw in Kanye West, you throw whoever in there and you just go with it and you roll."