The plot begins when narcotics agents Paul and Bobby are committed to putting an end to the drug syndicate known as "MID". MID's secret hideout is located on Riot Island, an island full of uninhabited ruins with people moved inside of it while turning it into a slum. Buildings include apartments, hospitals, factories and even a casino. During their heavy research on MID, they unexpectedly received a phone call from MID. When Paul heard the voice of his girlfriend Catherine crying for help on the phone while being hung up without explaining, he assumed she's been abducted, making him and Bobby head toward Riot Island and save her.
Gameplay
Riot City resembles Capcom's 1989 arcade hit, Final Fight, which is an archetypal side scrolling beat-em-up game. Player one controls Paul the blond-haired with balanced fighting skills, and Bobby the tough, but slowbreak-dancer from left to right through each level, fighting with the enemy characters who appear, until they reach a confrontation with a stronger boss character at the end of the level. Once that boss is beaten, the players automatically move on to the next stage. Enemies appear from both sides of the screen, and the players must defeat all of them to progress. If the players try to simply travel through the levels without fighting, the screen will stop scrolling until all current enemies have been defeated, before allowing the players to continue progress. Enemies may move outside the confines of the screen, but players may not. Unlike Final Fight, there are no weapons to pick upalong the way, but players will only pick up items for points.
While Westone decided to create a modified version of Sega's Wonder Boy for Hudson Soft as Adventure Island for the NES, they also took Riot City, remade and ported it to the TurboGrafx-CD as Riot Zone. The sprites of Paul and Bobby were modified and used for the main characters of Riot Zone, Hawk and Tony. Some parts of several Riot City stages were also recycled for use in Riot Zone. Unlike Riot City, Riot Zone lacks multiplayer and features high-quality music instead of chip-tune music.