Things start off with Carrie in Baghdad 10 months ago, where she bribes her way into a prison to retrieve information from a prisoner. We later find out that he told her that an American POW had been turned.
Cut to 10 months later, when an American POW has been saved and returned home to the U.S. Carrie immediately thinks he is a terrorist and illegally sets up surveillance equipment at his house.
Nick Brody, the rescued American, comes home to a wife and two kids. His wife Jessica has been with Nick's friend Mike for a while now, but nobody knows. Nick has a bit of trouble getting acclimated to his previous life, and has flashbacks to his time in Iraq.
While on camera, Nick gives some sort of signal with his fingers, at least that's what Carrie thinks he is doing. She sets out to figure out what it means.