The Adventures of Bayou Billy is an action game released by Konami for the Nintendo Entertainment System in North America in 1989 and in the PAL region in 1991.

The majority of the game follows a side-scrolling beat-'em-up format in which the player character (Billy) must engage in hand-to-hand combat against every enemy he encounters in order to proceed from one area to the next until reaching the end of each stage before his health runs out.

The player can also arm Billy with one of three melee weapons dropped by certain enemies: a throwing knife, a club and a whip.

While the majority of the enemies in the beat-'em-up stages are human bad guys, the player will occasionally fight animals as well such as crocodiles, eagles and guard dogs.

The game was originally released for the Famicom in Japan under the title of Mad City and was retitled The Adventures of Bayou Billy when it was converted to the NES for the international market, undergoing many extensive changes during the localization process.

Enemy characters and backgrounds are colored differently and the game's heroine, Annabelle, wears more revealing clothing in the NES version (having been changed from a v-neck dress to denim shorts and a midriff-revealing T-shirt).

Annabelle Lane (who is renamed Annabel Lee) also appears in the comic as an assistant district attorney who becomes romantically involved with Billy after being rescued from Gordon's lackeys.

Mother Brain had Dr. Wily build a robot cat to have Duke lead Captain N to Bayou Billy's world.