Catfish comes in at 89 minutes—just long enough to sustain the suspense in a setup that starts to play out like pure vérité horror (or “reality thriller,” as it’s being billed), just short enough to retreat from the squirmy destination it arrives at without going further than an ogle and the meaningless non-explanation of the title metaphor. Nev Schulman, a New York City photographer, begins a Facebook relationship with a precocious eight-year-old painter living in Michigan—then her mother, and her flirtatious 19-year-old sister. The entire process, including a developing Inbox courtship with sis Megan, is documented by Schulman’s brother, Ariel, and friend, Henry Joost. Why keep a camera trained on those chat boxes? And why is every fresh revelation toward Nev and Megan’s eventual meeting so well-staged? There is much here that is hard to swallow—if the viewer is being fished in, and how honest is the filmmakers’ surprise at the surprise twists of Catfish, are things known only to them and God. Whatever the case, the result is a briskly paced and callow film, with its perhaps-unintended subject the yearning for fame and appreciation—the quiet self-pitying desperation of the Michigan Sunday painter, and the loud self-congratulatory desperation of the Schulmans in Manhattan.