The husband of aviation engineer Kyle Pratt has just died in Berlin. Now she is flying back to New York with his coffin and their six-year-old daughter Julia. Three hours into the flight Kyle awakens to find that Julia is gone! It's a big double-decker plane, so very concerned mother has a lot of territory to cover in order to find her daughter. But as Kyle fights to discern the truth, she takes matters into her own hands.

In February, 2001, Robert Hanssen, a senior agent with 25 years in the FBI, is arrested for spying. Jump back two months: Eric O'Neill, a computer specialist who wants to be made an agent is assigned to clerk for Hanssen and to write down everything Hanssen does. O'Neill's told it's an investigation of Hanssen's sexual habits. Within weeks, the crusty Hanssen, a devout Catholic, has warmed to O'Neill, who grows to respect Hanssen. O'Neill's wife resents Hanssen's intrusiveness; the personal and professional stakes get higher. How they catch Hanssen and why he spies become the film's story. Can O'Neill help catch red-handed "the worst spy in history" and hold onto his personal life?