Scooby-Doo Mystery Mayhem follows the gang as they travel to the fictional town of Spooky Island. The group soon discovers that their hotel is haunted by a ghost, and it's up to Scooby and his friends to uncover the mystery behind the haunting.
Gameplay involves exploring levels, solving puzzles, and battling ghosts using various weapons and abilities. Players control Scooby as he navigates through levels, with the help of his friends Shaggy, Velma, Daphne, and Fred. The game features a variety of environments, including haunted mansions, spooky forests, and ancient ruins.