Vance assigns McGee, Torres, and Bishop to Covid compliance duty at a foreign affairs summit, where they discover a link to another NCIS team's murder case.

Evidence from the stabbing of a Marine Sergeant leads Torres to meet his father who left when he was a child.

When members of an NCIS Regional Enforcement Action Capabilities Training Team (REACT) are killed during an explosion, NCIS Special Agent Jessica Knight (Katrina Law), the lone surviving member, helps crack the case using high tech body armor.

While pursuing a dangerous arms dealer, the team is shocked when Bishop is implicated in an old NSA leak while Gibbs and Marcie realize the killer they've been tracking may be onto them.

As the NCIS team searches for Gibbs after wreckage from his boat is discovered, they find out he was tracking a serial killer with journalist Marcie Warren, who wrote an exposé on him.

While trying to find the serial killer Gibbs was after, the NCIS team discovers another person has been tracking the case as well.

Gibbs and McGee head to Alaska while the team works at home to uncover the conspiracy behind the serial killer.