The plot follows Jerry Shaw (Shia LaBeouf) and Rachel Holloman (Michelle Monaghan), two strangers brought together by a mysterious phone call from a woman they have never met. Threatening their lives and their families, the caller uses everyday technology to track and control their every move. As they are pushed into a series of increasingly dangerous situations, they must work together to uncover the identity of their tormentor and stop a massive political assassination.

Stars Shia LaBeouf, Michelle Monaghan, Billy Bob Thornton, Rosario Dawson, and Michael Chiklis.