As part of the announcement that Ralph Dibny, aka the Elongated Man, will be joining the the Arrowverse in Season 4 of The Flash, the official release compared the character's detective skills to none other than Batman. And while that was more likely intended to be used as a shorthand way of letting casual viewers know just how formidable Dibny's skills are, it did get us thinking. Yes, it's been merely hinted at for years, but is it possible that Batman actually exists in the DC Comics television universe?
That Bludhaven Connection
The hints that the Dark Knight is operating in some capacity in the Arrowverse aren't exactly new. His presence has been felt in small ways since the first season of Arrow, way back in 2012. Bludhaven, the city that once was (and is again) the home of Nightwing in the comics, shows up in the show far too frequently to be a mere Easter egg, and has done so since the very beginning.
Bludhaven is seen in the Season 1 episode of Arrow titled "Honor Thy Father," when Oliver threatens an embezzler to return his employees' pensions. Oliver mentions the city again in "An Innocent Man" two episodes later.
In "Dead to Rights," China White meets with Deadshot in the Bludhaven Apartments in order to contract him to kill Malcolm Merlyn. Late in Season 1, Malcolm also holds Walter Steele hostage within the city. The city gets name dropped again in Season 2's "The Man Under The Hood" and "Unthinkable."
In the comics, Bludhaven is established as the sister city of Gotham, which perhaps explains why it shows up so often in Arrow. The show practically takes the Batman template and places it over Green Arrow, so it makes sense it would take Bludhaven as well. It's also established in the in-universe tie-in comic that a train runs from one city to the other. Clearly, Starling City (or Star City) as a stand-in for Gotham City is more than just a fan theory.
It would be easy to pass this off as nothing but fan service, and yet Bludhaven just won't go away. In the Season 3 episode of The Flash, "Attack on Gorilla City," Julian Albert mentions a conference in Bludhaven that provides the perfect cover for both him and Barry Allen to travel to Earth 2 without having to worry about their jobs.
The Wayne Name
The first confirmation that the Wayne family exists in Arrowverse continuity comes as a tiny Easter egg in The Flash's 2014 pilot episode. When the fake Harrison Wells reveals himself to the audience at the end of the episode, he cues up a newspaper headline from the year 2024 detailing the disappearance of the Flash in some kind of crisis.
If you're a fan of the show, you remember the future newspaper and its revelation, but what you may have missed was the accompanying story published on the same page. At the bottom of the page is an article covering the merger of Wayne Tech and Queen Inc. We can assume that Queen Inc. is some future incarnation of Queen Consolidated, while Wayne Tech seems to confirm the existence of the Waynes.
The name sticks around when we find out in "Power Outage" that the merger failed in an alternate future. It's also mentioned again in "The Trap."
My Friend Bruce
The Flash showrunners get a little more daring in the 2015 season 2 episode "Welcome to Earth 2" by dropping the name Bruce. The technology on Earth 2 is shown to be a little different than it is on Earth 1; specifically to this point, on this Earth, people still use push-button desk phones. Barry's phone is shown to have contacts that include "Dad" (Joe West), "Mom & Dad" (his biological parents), and "Eddie" (the counterpart to Iris's Earth 1 boyfriend).
The remaining three contacts on the phone add a little bit of fun and intrigue. The names Bruce, Hal and Diana don't correspond to anyone on the show, but they do correspond to Batman (Bruce Wayne), Green Lantern (Hal Jordan), and Wonder Woman (Diana Prince).
Do these names actually correspond to other unnamed Earth 2 superheroes? We don't know, but it's a pretty big breadcrumb!