Superman & Lois’ latest episode may have revealed the show’s explanation for its evil Superman. It was previously established through John Henry Irons’ Arrowverse backstory that he comes from a world where Kal-El (Tyler Hoechlin) betrayed humanity and led an army of Kryptonian warriors in an invasion of Earth.
Because of this, Irons (Wolé Parks) has been dedicated to killing Superman, having become convinced that Earth-Prime’s Superman is destined to take the same path as the one from his world. However, characters like Lois Lane (Elizabeth Tulloch) have absolutely no doubts regarding Superman’s moral convictions and his devotion to protecting people. Given who this version of Clark Kent is, a twist where he suddenly abandons his ideals, dons a black suit, and goes on the attack does seem impossible to fathom (even though DC has done evil Superman stories before).
That being said, what happened to make the Clark Kent from Irons’ Earth turn bad remains a mystery. While the most obvious reason would be that he had a different upbringing, a totally different origin was seemingly hinted at in Superman & Lois season 1, episode 8, "Holding the Wrench”. It’s already been confirmed that X-Kryptonite, a variant of the green Kryptonite, can give humans Kryptonian powers, such as heat-ray vision and super speed. Now, it’s been suggested by Lois that these minerals do much more than that. Since Derek Powell and Rosetti apparently had their personalities altered by the acquisition of their powers, Lois thinks that the X-Kryptonite is actually causing these people to be possessed by the spirits of actual Kryptonians.
That theory points to what really happened with the alternate Earth Superman. Not only does it explain where that Kryptonian army came from but it also makes sense of his evil transformation. The implication thus far has been that X-Kryptonite works on humans, but there is no proof as of yet on what it might to do someone who is already a Kryptonian. If it could work on Superman, that might mean that he could end up being controlled by a member of his dead race, such as General Zod or some other Kryptonian villain.
If that’s true, that would be yet another indicator of Superman’s inherent good nature, and the notion that he won’t become turn his back on humanity no matter what. And it would provide further proof that Irons is wrong about Superman in every aspect. However, one major downside to this theory being correct is that it makes Clark Kent becoming a weapon of Morgan Edge (Adam Rayner) a real possibility for Superman & Lois season 1. This is an outcome that hopefully Irons, the Kents, and the government can prevent if they work together to stop what Edge is planning. Otherwise, they could lose their best chance of beating him.