"The K-Metal from Krypton" is an unpublished Superman story written by Jerry Siegel in 1940 and originally illustrated by the Joe Shuster Studio. Although the comic contained story developments that DC Comics (National Comics at the time) may have ultimately concluded could be potentially damaging to the franchise, the reason that the story was never published is not known. This storyline features the precursor to Kryptonite called "K-Metal" and Lois learns that Clark Kent is Superman; thus helping him with his escapes and his adventures. This might have altered the status quo from that point on.