Then, one night Kale sees something that looks like violence, possibly even murder, at Turner's house. With the help of cutting-edge surveillance gizmos - computers, walkie-talkies, designer cell-phone rings - available at their fingertips, the three start digging deeper into Turner's life, suspecting that he may be an elusive serial killer.

It takes a long time for "Disturbia" to going; the first act is devoted entirely to Kale's puttering around and restricted voyeurism. Director D.J. Caruso (Two for the Money, Taking Lives, The Salton Sea) waters down the material to best match the intended teen audience and works in a highly caffeinated romance between Kale and Ashley. But when the time comes for the film to go haywire, Caruso amps up the violence and grisly details sufficiently.

The script, by Christopher B. Landon and Carl Ellsworth, is not particularly brainy or original. But that doesn't really matter when you can deliver scares and fun, and Disturbia fulfills both with seeming effortlessness. To a certain point, this type of movie requires suspension of belief. Still, Caruso pulls all of the elements together to make the movie build to such a satisfying roller coaster of an ending.