Finch and Reese try to protect a psychologist who uses unorthodox methods to help patients achieve closure; flashbacks reveal Finch's state of mind after the death of his best friend.
Holmes and Watson search for an ulterior motive when Cassie Lenue, a brilliant young criminal whom they helped put in prison, seeks their help in solving a murder.
A woman with a rare disease surfaces in Massachusetts and brings illness and death to everyone she encounters.
Jackie and Danny think a young woman was forced to commit suicide; Frank clashes with Mayor Poole over a threat to the city; Henry has a heart attack.
FBI computers are hacked, revealing confidential files that make Alex think a second bomb is somewhere in New York; the recruits receive individual assignments that turn out to be connected.