"As important as it is to capture the essence of the character on an emotional level, there's an incredible physicality to these characters. So to see a kid who is a gymnast, and you know you're going to be digitally mapping to his movements... to have somebody who can move that way, it's f-ing invaluable. That's why everybody goes, 'Well, yeah, we have to see that,' If he can do that, that's a whole other asset that he's bringing, a whole other dimension that he's bringing to the part."