Full Name: Kai Samezu
Ranger Designation: GaoBlue
Title: Surging Shark
Weapons: Beast King Sword, Shark Cutters
Gear: G-Phone
Special Attacks: Surging Chopper, Iron Twister (With GaoBlack), Giraffe Typhoon, Giraffe Cutter, Surging Thrust, Surging Slash (With Eagle Sword)
Power Animals: Gao Shark, Gao Giraffe
Kai, who was nineteen when the journey began, his previous jobs included pizza delivery and working as a clerk in a bowling alley. He was considered a freeter, which is a Japanese expression for people between the age of fifteen and thirty-four who are unemployed or lack full time employment. Even though the team calls him only Blue, he freely introduces himself by name sometimes. He was chosen as a Gaoranger around the same time as Sae. He is a very energetic and playful guy, but he hates being treated as or called a child. His motto is "Never give up!" which he frequently uses to encourage Soutarou. He had precognitive dreams from Gao Giraffe that led him to defeat Boat Org. He is skilled at bowling and studied under a professional bowler, Don Katayama. To defeat Bowling Org, Kai needed to learn the tornado spin. He returned to Don for training, but it took some real convincing to get the disgruntled pro to teach Kai the move. After the final battle, he returned his G-Phone and jacket to Tetomu and became a clerk in a surf shop although he and Soutarou initially planned to run a Chanko shop together to "dominate the world."

Later in 'Hurricanger vs Gaoranger', he was kidnapped with his former team members by Tsuetsue and Yabaiba and their G-Phones were given to the Jakanja. He was impersonated by Windenu of the Jakanja. They escaped with the help of the Hurricanger, Goraijer and Shurikenger and defeated Tsuetsue and Yabaiba and the Jakanja.