Plot twists are something that have been very common in superhero movies and TV shows. After all, they can be what helps keep things fresh as the season or series goes on. When the Superman & Lois series debut on the CW, many fans rightfully assumed that this show was part of the overall Arrowverse. The reason for this was that the two main stars were the same actors from the Arrowverse (which had been merged together via Crisis on Infinite Earths) and there were other hints that it was on what is now known as Earth-Prime.
However, in the Superman & Lois Season 2 finale, a plot twist that has very much divided the fanbase came forward. Mainly in that when the cataclysmic event of the season started to unfold, one of the characters mentioned that Superman was the only true superhero on the planet. Which meant no Flash, no Black Lightning, no Supergirl, and so on. This was later reaffirmed by another character and fans rightfully expressed their displeasure.
Why? Because again, they had all sorts of hints about the other Arrowverse shows, including in how both Superman & Lois acted on certain “Crisis” matters. Furthermore, they brought in the beloved fan-favorite character Diggle to cameo in seasons 1 & 2, and both times we saw him reference his life in the Arrowverse, including a “quest” he had been going on that was “solved” recently in The Flash.
According to the showrunner, the plan was ALWAYS to be separated and to ensure this was another Earth in the Multiverse. The problem for fans is that they didn’t explain this from the beginning. If they did, it would’ve smoothed a lot of things over and not left fans wondering why Supergirl and other key characters didn’t come to save Superman in key situations.
Just as bad though, is that this means there’s only one true Arrowverse show left in The Flash. As Stargirl isn’t attached to the Arrowverse either (yet) and all the other shows have been canceled.
Source: Screenrant
