Surprisingly, Kryptonite didn't debut in the comics. The mysterious crystal was mentioned for the first time in the radio serial, The Adventures of Superman, which ran for 2,088 episodes over a period of nine years. Kryptonite debuted in the 1943 episode, The Meteor from Krypton. It didn't appear in the comics for another six years.
But how did the concept of Superman's iconic weakness come to be? According to the comic book editor, Julius Schwarz, Superman voice actor, Bud Collyer, was unavailable for recording his dialogue one day, causing the studio to panic. Since listeners were expecting to hear another one of The Man of Steel's incredible adventures, the studio had to improvise. During the episode's time slot, a radio announcement was made, stating that Superman was unavailable due to being incapacitated by a radioactive meteor.
And that is the origin of Kryptonite... or so the story goes. According to the historian, Michael J. Hayde, Superman doesn't encounter Kryptonite in the episode in question, The Meteor from Krypton. Instead, the real reason Kryptonite was introduced into the story was so Superman could learn about his home planet. Speaking of which...
James Egan is on YouTube under Comic Kong with new videos every week. He has written 15 books about comics
1000 Facts about Superheroes Vol. 1-3
1000 Facts about Supervillains Vol. 1-3
1000 Facts about Comic Book Characters Vol. 1-3
1000 Facts about Comic Books Vol. 1-3
1000 Facts about Superhero Movies Vol. 1-3
Twitter - @jameswzegan85