I det följande i den första Superman-filmen (1978) har Lex Luther följande:
You mean, to us, they're just meteorites. Fair enough. But the level of specific radioactivity is so high, to anyone from the planet Krypton, this substance is lethal!
Lex skjuter nu sin kryptonit i en leddlåda. Superman avslöjade för Lois Lane att han inte kunde se genom bly, som hon senare publicerade i sitt papper. Superman var nog inte smart att göra det.
I DCAU "En liten bit av hemmet"
Superman's attempts to stop the criminals are progressing nicely until he comes near a display of minerals. He sinks to the ground in pain, allowing the criminals to escape.
Luthor discovers the phenomenon and has the display analyzed to discover what happened to Superman. He learns that one of the rocks is from an foreign solar system and realizes that he now has the perfect weapon against Superman.
Å andra sidan, om du kan tro på en komisk omslag, så ja, Superman är en idiot som avslöjar sina svagheter mot sina fiender.