The Adventures of Superman (radio) home planet of Krypton is located on the far side of the sun, as opposed to a distant star system as it is in most stories. During the journey to Earth, baby Kal-el grows into an adult and emerges fully grown from his ship after it lands on Earth. He is never adopted by the Kents but immediately begins his superhero career. This was eventually retconned in later episodes to match the narrative of the comic books. This serial introduced the fictional mineral kryptonite, the radiation from which can weaken and even (in some continuities) kill Superman. Aside from giving
Superman II to Jor-El and General Zod. He finds Zod at the White House and tells him Superman is the son of Jor-El, their jailer, and offers to lead him to Superman in exchange for control of Australia. The three Kryptonians ally with Luthor and go to the offices of the "Daily Planet". Superman arrives, after having found the green crystal that restores his powers, and battles the three. Zod realizes Superman cares for the humans and takes advantage of this by threatening bystanders. Superman realizes the only way to stop Zod and the others is to lure them to the Fortress.