Downtown Nekketsu Monogatari (also known as River City Ransom in the American version) is an action game in the beat 'em up genre, where players must fight against numerous enemies who attack them on the streets or in various locations. Players can move by walking, running, jumping, and attacking. Developed by Technōs Japan and released in 1986 for the Nintendo Entertainment System (NES) or Famicom in Japan, the game became very popular at the time and is considered one of the standout games of the 8-bit era.

In this game, players take on the role of Alex (or Kunio-kun in Japan), a high school student who embarks on an adventure to rescue his girlfriend Riki (in the Japanese version) or Cindy (in the American version), who has been kidnapped and threatened by a gang. Players must travel through a crime-ridden city, fighting various enemies using both hand-to-hand combat and weapons, in order to save their friend and defeat enemies in every stage.