Alternative versions of Superman establish a new continuity for DC, affecting not only Superman, but all of the DC Comics characters. The versions of Superman from this time period are traditionally divided into three main periods. The first version of Superman began being published by DC Comics in 1938 appearing in "Action Comics" #1. To explain discrepancies in the aging of Superman across several decades, his earliest stories were retroactively portrayed as having taken place on an alternative world called Earth-Two. These stories take place from 1938 until the late 1950s, although the exact dividing line is unclear and some stories happened identically to
Superman in film 2015 documentary film "". Kevin Smith directed the ninth episode of the second season of "Supergirl", which was titled "Supergirl Lives" as homage to "Superman Lives". In November 2016, Kevin Smith said that he was open to having the "Superman Lives" script be adapted as an animated film, with Nicolas Cage voicing Superman and Michael Rooker voicing Lex Luthor. In October 2017, "Batman vs. Two-Face" writer Michael Jelenic stated that he originally pitched an animated film based on Smith's "Superman Lives" script, saying that Warner Bros seriously considered it for a long time. According to Jelenic, Cage would have loved