The CW has been hyping it's next highly anticipated Arrowverse crossover for a good while now. It all started when it was first announced that Kate Kane, aka Batwoman, would be joining the television event, the first member of the Bat-family to be featured in this shared universe of DC characters.
The hype has only grew from there, when Ruby Rose was cast in the role. Then, it was later announced that on top of visiting Gotham City, Metropolis will also play a part in the crossover: not only will Kara Zor-El's Supergirl be involved in the event, her cousin Kal-El, played by Tyler Hoechlin, also plays a role. Hoechlin, who was last seen as Superman in the Season 2 finale of Supergirl, will finally interact with Green Arrow and the Flash.
On top of that, actress Elizabeth Tulloch was cast in the role of Lois Lane for the event. And, it all that weren't enough, this week brought a one-two punch sequence of surprising news. First, the crossover finally has a name: "Elseworlds." And, perhaps even more significantly, LaMonica Garrett will play Mar Novu, a powerful alien known as the Monitor.
At first, fans expected that this latest Arrowverse crossover would tone things down from pervious events and focus on Gotham City and the rise of Batwoman. However, that no longer appears to be the case. With the title "Elseworlds" and the addition of the Monitor, it appears that the heroes of the Arrow Multiverse will once again be facing a crisis of cosmic proportions. In fact, the Monitor's involvement strongly suggests the story will end things with a Crisis on Infinite Earths-type of event -- could this be the device by which the Arrowverse merges Supergirl and Arrow's respective Earths together?
First off, let's focus on the newly-revealed title of the Arrowverse crossover, "Elseworlds." In the publishing world of DC Comics, Elseworlds is a brand, an imprint that signifies that a particular story takes place in a separate reality than the main DC continuity. The brand of Elseworlds typically applies to self-contained graphic novels that examine an alternate reality where things are generally much different. For that reason, the Elseworlds realities have often been considered to take place in other universes that constitute the massive DC Multiverse.
The DC Multiverse is a concept that was actually established during the second season of The Flash. There, we saw that the Earth Oliver Queen and Barry Allen inhabit is known as Earth-1, and that there are multiple alternate Earths, with different histories and their own versions of superheroes such as the Flash. One of those Earths is actually Earth-38, home of the series Supergirl. This Earth was actually born out of necessity: when Supergirl first premiered, it was on the CBS network.
However, after the conclusion of Season 1, the series was moved to the CW, where it was retroactively roped into the Arrowverse. Now, whenever there was a big crossover such as 2016's "Invasion!" or last year's "Crisis on Earth-X," the storyline had to find a way for certain characters to breach the barriers between realities in order to be brought together to fight a common threat. On The Flash, we've seen small instances of other Earths, such as Earth-3 and Earth-48. Then, in the 2017 crossover "Crisis on Earth-X," we learned that there were 53 universes in total.
And this brings us to the Monitor.