Shawn Thomsen

The team face the return of a serial killer whose mind games continue to complicate their investigations.

O'ahu goes on lockdown as the team look for a terrorist who is using weaponised drones on civilians; McGarrett and Danno attend a review with a psychologist.

Following McGarrett and Wo Fat's escape, gunmen hit Five-0 headquarters; McGarrett must turn on his own in order to find Catherine.

McGarrett searches for the people who are responsible for the death of his CIA agent friend. Plus, Tani questions whether she should tell McGarrett about the murder weapon she found at Adam's house.

When a man from Detroit is killed on the streets of Oahu, the team are shocked to discover the killer's motives; Chin risks everything to help Danny.

The murder of a swimming pool cleaner leads the Five-0 to a cell of radicalised students plotting an attack on US soil.