The psycho kid flick -- from The Bad Seed to The Good Son -- tends to wallow in precocious camp and cheap devil-child thrills. George Ratliff's Joshua attempts to revitalize the genre by injecting an element of realism. When his mom, Abby (Vera Farmiga), and dad, Brad (Sam Rockwell), give birth to a baby girl, Joshua (Jacob Kogan) starts to worry that not only will he have to share attention with his sister, but that his flowering sociopathic tendencies will alienate him from his parents. A Bartok-loving piano prodigy who is terrible at sports and a model student, Joshua is the kind of sensitive but bright young boy routinely ostracized for his intelligence. He worries about being "weird," a stranger in his own home. Could such a kid really be ripe for serial killing? At its scariest, during the slow build of offscreen "accidents," Joshua plays off the neuroses of the child's neo-yuppie Upper East Side parents. Abby, acting out a kind of postpartum Rosemary's Baby, gradually goes insane trying to care for the newborn, who won't stop crying, and Brad soon follows. Is Joshua threatening the baby? Rockwell delivers the most tonally appropriate performance as Brad, the kind of well-meaning iPod-sporting dad who is sympathetic and annoyingly self-centered at the same time. There is a dirty thrill in watching his world fall apart, but the insanity quickly gets irritating. There's a lot of screeching. Whether or not a parent is acting "crazy" in a given scene is indicated by their hair sticking up in thick-gelled clumps. The primary problem, however, is that Joshua's psychological manipulations take place almost entirely offscreen. This works at the beginning, when the slow-moving dolly shots and teasing frames play with our anxieties. But the tension never builds past the first act, there are no confrontations with the child, and all we are left with is his silent presence -- no longer enigmatic but frustratingly inert. The end result is neither realistic, campy, nor scary, just boring and ridiculous.