Jim is the first boss from Double Dragon 3: The Rosetta Stone/The Sacred Stones. The younger brother of Willy Mackey, Jim is the leader and founder of the Neo Black Warriors, which he formed after the original Black Warriors led by his brother were defeated by the Lee brothers. As such, Jim seeks revenge on the two for the death of his brother, attacking the brother's dojo in the first stage of the game.

Unlike his brother, Jim prefers to fight bare-fisted, being known for his Flying Knee Kick. In the original version of the game, his only role is to serve as the first boss, while in the Famicom version of the game, his Neo Black Warriors are responsible for killing the Lee brother's friend Aldo/Brett.