John Turtletaub breaks down the "mop sequence" in The Sorcerer's Apprentice

MakingOf: Can you walk us through the mop scene and how you actually brought that to life?

Jon Turteltaub: Its starts with the original ‘Fantasia’ piece with Mickey Mouse and watching it over and over and over again. Watching it with the cinematographer and with the composer and really understanding what made that so great. Then you go to the writer whose finding a way to put that scene in the context of the whole movie because we have to approach it from the point of view of what’s the character of Dave doing in this scene? Why is it important to clean up this whole space quickly? Then we go about shooting it. You plan and plan and plan. You have to know where everything’s going to be You have to build a set that can have water fill it up and have water drained quickly so you can fill it and drain it. It’s a lot of prep. You go out there and you know what your shots are for the most part, and you take a bunch of people in green body suits and you give them mops and brooms and tell them to start brooming things and mopping things. If your going to smush water around you want to really smush the water, you want the light to really be on that set. When things explode and there’s electricity there you need to know that the flashing light is real. Once you’ve shot all the real stuff then you go back and do the visual effects part, and you’re animating, and you see a mop made of a pencil sketch of a little nothing, and then comes a short of 2D grey mop, and then it becomes a 3D mop, and then it has wood on it, and then you tell the guys its not working start over. Then you do it over and over again for 7 months and then hopefully you have a sequence.