Lex Luthor, who now disguises himself as a legitimate businessman, manufactures robotic machines called the Defendroids, which are supposedly designed to protect the citizens of Metropolis. Many citizens then make the claim that Superman is no longer needed, since Luthor's machines are more than enough to protect Metropolis. But soon it's realized by Superman that Luthor's real goal is to use the Defendroids to rob the city mint from a train, and then make the false claim that the robots had "short circuited." Superman is unable to prove Lex's involvement in the crime.