Marcus Mooney was a music producer and the owner of Moonrise Studios.
In the 1930s, Marcus allowed Willie Cole to record on an acetate. He left him to do so, but in the process the man was killed by The Devil, who had come for his promised soul. When Mooney came back, he discovered blood everywhere and hid the acetate within one of the walls of the studio.
Around 80 years later, Marcus was a resident of Devonshire Nursing Facility. He was visited by John Constantine and Zed Martin, who were asking about the acetate. He provided them with a clue, "Fell", before his life was peacefully taken by Manny.