Blue Valentine is essentially two excellent films in one: It’s a sweet, passionate romance, and it’s a blisteringly nasty breakup story. In one part of writer-director Derek Cianfrance’s film, we see Dean and Cindy (Ryan Gosling and Michelle Williams) magically falling in love and moving toward marriage. This portion is shot with a beautiful romantic grace, and is full of promise. In the other part, we see Dean and Cindy a few years down the road, and their marriage is a terrible mess. Each of them possesses only slight hints of the joy and happiness depicted in the earlier years, and the scenes are appropriately shot with a grainy, gritty look. Cianfrance interweaves the two periods—the happy past trades scenes with the grim future—and the effect is heartbreaking. Gosling and Williams are extraordinary, putting forth the kind of work most performers only dream of delivering.