Seymour "Blue Jaw" Magoon was an American hitman in New York's Murder Inc gang, one of many members who were implicated by the testimony of former member and government informant Abe "Kid Twist" Reles.
A longtime member of Murder Inc., Magoon was heavily involved in the painters unions with Martin "Buggsy" Goldstein during the 1920s and 30s. Magoon helped testify against the other members of Murder Inc., along with Albert "Tick Tock" Tannenbaum and Sholem Bernstein. To this day, few details exist about Seymour Magoon.