The team investigates the death of a scuba diver who was shot with a gun used in another murder on Hawaii Five-0. "Ua 'O'oloku Ke Anu I Na Manuna (The Chilling Storm Is On The Mountains)" is the third episode of the show's sixth season.
Russo: Hey, check this out. Steve: What was inside? Russo: Cyanide Steve: Cyanide? Russo: I know, crazy right? The secret bunker, the World War II pistol, the kill pill, and the ring with the in compartment, this is some real secret agent stuff.