 One day on makunai island (off the coast of Japan) Ryu receives a letter from his pen pal from the United States, Ken. It is an invitation for Ryu to come to meet Ken in San Francisco. Ryu accepts this invitation. When Ryu arrives in San Francisco, Ken picks him up and brings him to his house. Then, at night, Ken decides to scope San Francisco for bars, then Ken flirts with one of the air force pilots  girlfriends and gets into a fight. Ken defeats the pilot, but he and Ryu are unaware of their next opponent.