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.
Superman II the sequel, but he declined out of loyalty to Donner. He recounted "I have a lot of respect for him. [referring to Richard Lester] Friendship is more important than anything. And Dick [Donner] brought me on the picture and my loyalty was with Dick and I couldn't believe that they fired him." Editor Stuart Baird also declined to return for the sequel. Gene Hackman declined to return for re-shoots, which necessitated the need for a stand-in actor and a voice double for several scenes. To replace Mankiewicz, "Superman" co-screenwriters David and Leslie Newman were then brought back to re-tool the