“Ema” offers no narrative sleights of hand, and it follows its lead as she undertakes her plan without resorting to plot twists or shocking reveals. And though Larraín doesn’t hide anything, he tells the story with an offbeat style that presents images without necessarily telegraphing their importance within the larger plot — in essence, pushing “show, don’t tell” so far so that every that every viewer will come to understand the main character’s larger plans at a different point in the film.