Shot in black and white, this eccentric Mexican comedy by first-time director Fernando Eimbcke focuses on two 14-year-old boys left to themselves in an urban high-rise on a Sunday afternoon. A 16-year-old neighbor comes over to bake herself a birthday cake, and an alienated pizza delivery man hangs around on various pretexts. The characters’ behavior isn’t always believable, and the jerky rhythm takes some getting used to (there may be more attitude here than observation). But the defiant absence of any conventional plot has a cumulative charm. In Spanish with subtitles. R, 85 min. (JR)