After an early morning Tsunami alert, McGarrett and Danny get called to the Tsunami Warning Center because its Director has gone missing. The timing of the disappearance couldn't be worse as there's a lot of conflicting data about the Tsunami that the Deputy Director doesn't know how to interpret and Captain Mike Hale from the Coast Guard needs a threat level from the Deputy Director to activate his services as to the best plan of action. Chin Ho and Kono search the Director's house and determine that he's been abducted but is probably still alive. They also realize the Director was trying to send a message, but they can't decode what it means. As the rest of the Police Dept. helps the islanders seek higher ground and move inland for safety, McGarrett and the team (with a little help from McGarrett's girlfriend in Naval Intelligence) track down and rescue the Director. They also figure out the tsunami was a ruse perpetrated by Captain Hale in order for him to steal money from the HPD evidence locker. When the Five-0 team realizes that catching Captain Hale means HPD will figure there's $10 million missing (Five-0 took it and it to rescue Chin Ho, but Victor Hesse burned it) and they'll be caught, they decide to do the right thing and get Hale. In the end, McGarrett gets called to the Governor's office; the team joins him as they're all in it together. McGarrett gets out of the meeting saying the Governor congratulated them on a job well done, and mysteriously, the money is all accounted for.