Winner of the Un Certain Regard best director prize at Cannes 2013, Alain Guiraudie’s Stranger by the Lake is a slow, lovely, aggressively sexy movie with a brilliantly black heart. The story: At a lakeside cruising spot in France, a cute twentysomething gay man makes two new connections. One is a friendly, chatty older guy, the other a sexy cruiser with a passion for compartmentalized sex. Before long, a body is found, an investigator starts snooping around, and Stranger by the Lake turns into something deep and terrifying, dealing both literally and conceptually with notions of sex, risk, danger, and the moral apathy of the horny. (SIFF Cinema Uptown, 511 Queen Anne Ave N, siff.net, 5, 7:15, and 9:30 pm, March 7-13)