The death of a professional tennis player leads the task force to a doctor who may be fixing the odds for a major sports betting syndicate; Red digs deeper into Dembe's betrayal; Ressler struggles with sobriety.

In a series of flashbacks, Donald Ressler recalls his actions in the aftermath of Elizabeth Keen's death.

The task force investigates a therapist who may be the key to the resurgence of an organized crime family; Red conducts an investigation of his own.

Dembe's position as an FBI agent causes complications for Red as the task force handles a case involving military technology; Cooper and Park each find their personal lives increasingly complicated.

The task force races to locate a blacklister who uses any means necessary to return what has been unjustly stolen; Ressler asks Park for a favor; Cooper tries to piece together an event for which he has no memory.

A new case involving stolen artifacts reunites Red with a former blacklister; Aram faces a difficult decision.

A kidnapping poses a test for the capabilities of the task force as they contend with a mysterious pirating organization.