Biblioteca Marvel Thor nº4

Loki uses his magic to cause Thor's hammer to hit his head, turning him evil. Thor frees Loki, and the two terrorize Earth until the other Asgardians arrange for another blow to the head to reverse the change.

An evil scientist forces Dr. Blake to help him with a duplicating machine by kidnapping Jane. The device duplicates Thor, but cannot duplicate his magic hammer, allowing Thor to defeat the duplicate. Dr. Zaxton accidentally duplicates himself and falls to his death, leaving his good duplicate to take his place.

Merlin is awakened after a thousand years and immediately decides to try and take over the world; He battles Thor using familiar Washington D.C. monuments. Thor defeats Merlin and forces him to return to sleep.

Thor battles the Lava Man, a monster created by Loki who claims all the dry surface of Earth for his people. Odin forbids Thor to love Jane Foster, leading to her leaving her job as Dr. Blake's nurse.

While visiting India, Don Blake finds that one of his old teachers has been murdered by a villain who gained the power of a snake. Thor fights the Cobra in New York and defeats him, after Jane Foster sees her new boss's cowardice and goes back to Dr. Blake.

Having been refused a job by Dr. Blake, Calvin Zabo becomes Mister Hyde and attacks the doctor. Meanwhile, Odin has agreed to let Thor marry Jane Foster if she proves worthy. After Mister Hyde learns that Blake survived ('saved' by Thor) it seems that Thor robs a bank, and the police issue a warrant for his arrest.

Mister Hyde kidnaps Don Blake and Jane Foster and then tries to steal a submarine using Jane as a hostage. Jane stops Thor from catching Hyde because she thinks that Don is still in danger. The police realize that Hyde framed Thor for the bank robbery, but Jane's actions convince Odin that she is unworthy of immortality.