While Five-0 investigates the murder of a bounty hunter after he apprehended a fugitive hiding out in Hawaii, Rachel reveals a long-held secret to Danny that has serious ramifications. Also, as Kono’s wedding nears, Chin voices his concerns to McGarrett that Adam is still working with the Yakuza.

In order to stop a meth epidemic on the Island, McGarrett and Danny go undercover as pilots, but when McGarrett is seriously wounded, Danny is forced to break their cover in order to save his partner’s life.

Crime spikes when a heat wave hits Oahu, causing McGarrett and Danny to hunt down a bank thief, and Tani and Junior's car is stolen while they're on duty. Also, Grover plays the golf game of a lifetime, and Kamekona incites a riot by price-gouging on his shave ice.