Caroline Knight is a normal high school girl. However, her father, Michael, is a very important man. He works for the FBI, with the Federal Witness Protection Program. So when James Clark, a criminal/murderer, wants to know where someone is, he goes after him in hopes of finding out. But obviously, Michael won't tell him. James then decides to go after Michael's family. Which is where Special Agent Nick Sharpe comes in. He's sent to pose as a teacher at Caroline's high school in order to protect her. But he didn't think that while protecting her, he'd fall in love, too.