Maverick CIA agent Carrie Mathison doesn't like playing by the rules. Haunted by her failure to anticipate the 9/11 attacks, she is determined to ward off further terrorism against U.S. targets, almost at any cost. She is already skating on thin ice within the CIA after a disastrous attempt to get information from a condemned Iraqi source sparks a diplomatic crisis. But Carrie was able to get a small piece of unsettling secret intelligence from her source before he died, and she is convinced it has alarming significance to the return of MIA Sgt. Nicholas Brody. The crucial question is, is Carrie's conviction based on fact or is it the product of a delusional obsession?