Justin Peck dances in the corps de ballet, the lowliest group, at New York City Ballet. So he's not a star dancer. He is becoming a star choreographer. This documentary is the story of the rapid creation of his new work for 2013, from steps to costumes to lighting to opening night—when, after his piece, he goes down into the bowels of the theater and puts on cake makeup to go on in the second half. What you see is an artist at work, sometimes sure, sometimes open. It's actually riveting (72 min.). By Jen Graves