This is the first computer animated movie to be produced in real 3D instead of converting the film into 3D after it is finished.

Pictured above (from the left) are directors Rob Letterman, Lisa Stewart, Conrad Vernon. The latter, who also worked on 'Shrek' commented: "The 3D is really working well. It's pretty astounding. I've heard a lot of people say this is the first time it has really blended into the movie seamlessly".