The Man Called Merc is a side-scrolling beat 'em up, where players control the titular Merc, a mysterious and deadly man-for-hire, as he fights his way through hordes of cybernetic monstrosities in the fictional Talgore City. The game's visuals are stylised in a noir graphic novel style, making use of a black and white art style, with the only colours being emitted from the nyon energy found throughout the city. Keeping with the art style, the game's story is also told in graphic novel fashion between levels, slowly unfurling the mystery.

Usually found on an assassination mission, or an intricately plotted bank robbery, the Merc has had a slow month of few job opportunities, and is currently working as a part-time nightclub bouncer. One non-descript night, and without reason, all hell breaks loose as the city suddenly erupts into chaos as legions of cyborg and mechanical killing machines begin destroying everything in their path. The Merc kicks into action, and begins his unexpected journey across the city to learn the origin of this chaos.