Robert Zemeckis lives in a Thomas Kinkade-style cottage in the wealthy creek-side district of the Uncanny Valley, a neighborhood where everything looks like a Parisian Christmas as reenacted by Precious Moments kids. At least, I imagine that’s where his hate mail goes—notes about the terribleness of matte-eyed, computer-generated movie protagonists with A-list voices, plus maybe a postcard from Disney about how they’re kicking Zemeckis’ production company off the lot. Zemeckis—who made killer stuff like Back to the Future and Forrest Gump before mo-cap disasters The...