Arrow launched an interconnected universe of shows for the CW when it premiered. Originally consisting of Arrow and The Flash, the Arrowverse grew to include Legends Of Tomorrow, Supergirl, Batwoman, and Black Lightning. The Arrowverse (or Berlantiverse, named for producer Greg Berlanti) added the series Superman & Lois to its lineup during the most recent television season. Previously, the title characters appeared as guest stars and supporting players in Supergirl and crossover events.

One of those crossover events was "Crisis On Infinite Earths." All of the shows, even those like Black Lightning set in alternate realities, were supposedly combined into one world as a result of timelines colliding. Now that Superman & Lois has aired its first batch of episodes, however, and Supergirl has returned for its final season, it doesn't seem like that's the case. The two series don't appear to take place in the same world at all. Superman is clearly set apart from Supergirl.

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Just five episodes into its first season, it's made clear that Superman & Lois ignores the greater Berlantiverse as a whole. That includes Supergirl. Other established series make mention of their heroic allies once in a while. Superman & Lois remains firmly focused on the family at the center of the action.

The series follows Clark Kent, his wife and journalist Lois Lane, and their twin sons as they make the decision to move to Smallville. A small town setting pulls them away from big city demands. Clark still dons his cape for heroics on the other side of the world but doesn't team up with others. In fact, he doesn't even mention them. Clark also doesn't mention his past adventures with them. That could easily be explained as not wanting to out his allies to his kids. It also might be more than that.

In the first two seasons of Supergirl, title character Kara Danvers kept in close contact with Clark Kent. The two regularly traded stories about their life. Kara took his advice about balancing her normal life with a hero persona. Clark even paid her a visit. There's been no acknowledgment that he even has a cousin in Superman & Lois. Even Lois never mentions her sister Lucy, who also made frequent appearances in the early seasons of Supergirl.

It might be safer for Superman & Lois to put a little distance between itself and Supergirl. Supergirl, after all, is currently airing its final season. Superman & Lois has another season ahead, renewed after only the airing of the first episode. Setting some distance between the two means fans won't be expecting Supergirl characters to visit when their show comes to an end.

It is, however, interesting that Supergirl most recently dealt with a Lex Luthor plot to take over the world, but Superman had no involvement. Instead, fans see Superman rescue neighbors from fires, restore collapsed bridges, and fly across the planet to prevent nuclear reactor meltdowns. Even though Superman can fly around the world to help others, he steers clear of events in National City altogether. This allows Kara and Clark to stand on their own.

While the distance makes sense to allow Superman & Lois its own time to grow as a series, it does create suspicions amongst fans. Does Supergirl still take place in the same world as Superman & Lois? There are a lot of differences between the two that can be chalked up to production timelines.

The Fortress Of Solitude, for example, is very different in both shows. Kara uses the Fortress throughout her series to communicate with an artificial intelligence version of her mother. Clark also uses it to communicate with his father. Both locations, however, are not the same. They differ greatly in set design. That could be chalked up to the different shows using different set pieces. Production teams operate independently of one another, and utilizing the same set could create logistical issues for the teams involved. It's not just the Fortress that presents a problem though.

The series features its own take on Alexander "Lex" Luthor. As the fallout from "Crisis" demonstrated for fans on Batwoman, two different Earth versions of the same character can't exist on the same world without one of them dying. That would indicate Supergirl's Lex is no more. Villains in Superman & Lois also make it a point to tell Clark he's "no longer alone" when they give Kryptonian abilities to a human. It's established that Superman and Supergirl have the same powers. If Superman is alone in the world, where is Supergirl?

As all of the possible Earths collided during the "Crisis On Infinite Earths" crossover, Lois and Clark had a single baby. They also resided in the floating city of Argos. "Crisis" destroys that timeline. In the new timeline created as a result of the crossover, the duo has two teenagers instead of a single infant they sent out in a pod to safety.

It's entirely possible that when the world resets, not all heroes reset equally. Perhaps Superman & Lois still exists in Supergirl's world, but it's no longer in her present day. With the end of Supergirl on the horizon and teenagers involved in Superman & Lois, it's not out of the realm of possibility that the latter actually takes place in the future.

If that's the case, Superman & Lois may present an indication of the path Supergirl takes to its ending. A retired Kara (or a displaced one) wouldn't be unusual. Neither would the death or disappearance of her supervillain. Eagle-eyed fans will have to keep an eye out for clues as to whether Superman & Lois is on a new Earth or not when new episodes return on May 18.

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