In Hollywood two men ambush a limousine and shoot the occupants to death; Hetty says that the target, Renner, was a Swiss antiques dealer and black marketeer; she persuades the LAPD to allow her to take over the investigation because of the nature of a little black book, which she believes is the object of the activity. While Hetty visits a man in an assisted-living place, G and Sam visit Renner's pad, which someone has tossed; Eric identifies a man, Lee, who appears in a number of photographs around Renner's house; G and Callen visit Lee's office and break up a meeting; Eric says that Lee's two visitors are German "agricultural attachés" (that is, spies); G and Sam question a retired operative, and Kensi and Deeks also search Renner's pad, where they meet two foreigners with alternate identities; Hetty visits the Hollywood Bowl, and the four musketeers rescue her. Hetty again calls on her elderly friend, whom she finds dead, executed by gunfire. [To be continued.]

Intrigue and violence continue while several parties search for the "little black bloody book". The team investigates Cole's shooting and find a link to the murder of a cop during a traffic stop.

The NCIS: LA team takes action to protect one of their own while being interrogated by the Department of Justice. Meanwhile, Nell goes undercover as Hetty, and Director Leon Vance gives Hetty disturbing news while she is in Washington.

The team goes beyond boundaries to make sure Hetty is safe but what they don't know is that Hetty has her own plan as always. Meanwhile Nell is having a hard time after having killed for the first time and is visited by a know face who might be able to help her.