Return to Krypton is a 2000s story arc, redefining the nature of Krypton. In the story, Superman begins to suspect that the version of Krypton he knows is not correct, and that the pre-crisis version may be the true Krypton. It was later revealed in a follow-up story, however, that this was Krypton as it had existed thousands of years prior to its destruction. This era was Jor-El's favorite time period, as it may explain why Jor-El favors Krypton's less-sterilized, more emotional days.