Junior and Adam back up McGarrett when a bank heist in progress forces Steve to make a potentially heartbreaking mistake. Also, Adam is forced to face an empty home without Kono.
A Christmas Eve ransomware attack on the Honolulu Police Department forces Lia (Chantal Thuy) to reveal a family secret to Magnum and Katsumoto.
Magnum and Higgins take a major step forward in their relationship; at the same time, the past comes back to haunt them when a previous suspect becomes their client; TC aims to scale up Island Hoppers; Rick gets a new business partner.
