A hunchback bald saboteur and spy he plotted with three other spies.
Calling themselves the Faultless Four they sought to steal an “Atomic Bombarder” (sic) and sell it for a million dollars to seven foreign powers. To this end they kidnapped Arthur Williams and tried to murder his daughter Joan.
He and the three were foiled by the Golden Age Flash. Sieur electrocuted the room killing the other three, but the Flash escaped. Sieur died in the end when he crashed his car as he tried to escape the Flash.
He was also the first foe of the original Flash.