If you came across an absolutely remarkable thing at 3 a.m. in New York City, would you walk away . . . or do the one thing that would change your life forever?

The Carls just appeared. Coming home from work at three a.m., twenty-three-year-old April May stumbles across a giant sculpture. Delighted by its appearance and craftsmanship - like a ten-foot-tall Transformer wearing a suit of samurai armour - April and her friend Andy make a video with it, which Andy uploads to YouTube. The ...