Sharon's son, Ricky, comes home for a surprise visit while Major Crimes investigates what looks like the "follow home" murder of a retired LAPD fraud detective, who may have been murdered for an arrest she made decades ago.

A murder investigation turns explosive while Captain Sharon Raydor duels with Chief Winnie Davis for control of her case as she and her squad try to determine if they are dealing with a terrorist. Meanwhile, Rusty gets some alarming news from Gus.