[SPOILER ALERT: Don't read this unless you want to know the twist behind 2010's craziest quasidocumentary that doesn't involve Joaquin Phoenix.] Young Manhattan filmmaker Nev Schulman has a fan: Abby, a precocious 8-year-old artist from rural Michigan. When their budding Facebook friendship is joined by her mother Angela and comely teenage half sister Megan, Nev and his brother Ariel drive to the Upper Peninsula to cement the connection. Catfish may or may not be a documentary, but it is certainly a portrait of something true: the need that real people have to create fictional versions of themselves. Angela Wesselman, an earnest Midwestern mom who pretended to be Abby, Megan and a score of other online personalities, is the imaginative novelist of her Internet life, and whether she is acting on camera or simply, poignantly "being," she has created a memorable character with a large, complex family of the mind.