Batman is yet to appear in the Arrowverse, but could that be because Bruce Wayne's retired - or worse? Gotham answers will surely come now that Batwoman is coming to the Arrowverse. The character will be introduced in this year's Arrowverse crossover event, which will also reveal the DCTV version of Gotham City.

The crossover will also serve as a back-door pilot for Caroline Dries's Batwoman TV show. Dries is no stranger to DCTV; she's worked with them before on Smallville. Assuming The CW execs approve of the pilot, the Batwoman TV series is expected to launch sometime in 2019.

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Batman has been referenced before in the Arrowverse, and some of his key villains have actually appeared in the various DCTV shows. But the decision to focus on Batwoman raises an interesting question; where is Batman himself? In the real world, TV production and distribution rights for the Dark Knight are actually owned by Fox. The network was responsible for the classic 1960s Batman series, and has retained those rights ever since (amusingly enough, that means that Disney's proposed purchase of the bulk of Fox's TV and film empire may see Disney gain the TV rights to Batman). But in-universe, what reason will be given for Batman's absence?

What We Know of the Arrowverse's Batman So Far

The first seasons of Arrow positioned Oliver Queen as a billionaire who uses his wealth to become a vigilante, going to war on crime. In terms of general tone and style, the series drew heavily upon Christopher Nolan's influential Dark Knight trilogyArrow was hardly subtle about its inspiration, even lampshading it in a number of scenes where Oliver quipped about the idea. "Well, you know us billionaire vigilantes," he snarked in the season 1 episode "An Innocent Man." "We do love our toys." That was only the first of these puns, and while it's never been stated that Oliver has met Bruce Wayne, let alone that he knows Batman's secret identity, the comments have brought delight to viewers. Of course, these are all meta gags: there have also been a number of scenes where hero's symbols have been projected into the sky, with the characters joking that they got the idea from a comic book.

Little by little, though, various references began suggested that Batman exists in Arrow's universe - and that he's been active as a vigilante for quite some time, with a well-developed rogues' gallery and a number of key friends and allies. Arrow season 2 had nods to Harley Quinn, with a deleted scene for season 2's "Unthinkable" showing Harley begging Diggle to free her from A.R.G.U.S.. Arrow had big plans for Harley Quinn, until higher-ups at Warner Bros. asked the show to back away in light of the Suicide Squad movie; they feared brand dilution could be a potential problem. Meanwhile, a running gag saw Felicity Smoak try to decide on a code-name, ruling out "Oracle" because it was already taken. Executive producer Wendy Mericle told TVLine that the Oracle name was "off the table," presumably in a similar way to the show's plans for Harley Quinn, but it didn't stop the showrunners taking a similar approach for Felicity when they crippled her. Most recently, Two-Face was referenced in the season 3 episode "Finish Line."

Gotham City itself has been referenced, too. The Flash season 2 episode "Flash of Two Worlds" included a blink-and-you'll-miss-it reference to Blackgate Penitentiary, a prison and genetic modification facility located on an island in Gotham Bay. This prison is distinct from DC's more famous Arkham Asylum, in that it holds Batman's criminal enemies rather than his insane foes.

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Among all this, there have been two direct references to the Waynes. In The Flash season 1 episode "The Trap," Barry and his friends look at a newspaper cutting from the future that reveals the Flash is destined to mysteriously disappear. Attentive viewers spotted another headline on the front page; "Wayne Tech/Queen Inc Merger Complete", suggesting in that particular future timeline - since averted - Queen Inc wound up owned by another billionaire vigilante. But the most explicit reference was in Arrow season 6, when Oliver name-dropped Bruce Wayne. Arguing that photos didn't prove he was really the Green Arrow, he pointed out that these can be doctored. "They could have put Bruce Wayne's head on that body," Oliver observed, before jokingly asking whether Wayne had left Gotham anytime recently. This was actually Stephen Amell's idea; the script originally just referenced another famous name. He approached Warner Bros. execs with the idea of throwing in a Bruce Wayne reference, and they signed off on it.

Putting all these pieces together, then, we know that the Arrowverse's Bruce Wayne is indeed Batman, and Wayne was still active as recently as Arrow season 6. The Dark Knight's vigilante career has clearly been going on for a while, as several of his key friends and enemies have taken on their roles; in the comics, Barbara Gordon adopted the codename Oracle after she was crippled by the Joker, while Harley Quinn was originally the Joker's therapist; both references suggest even the Clown Prince of Crime is out there in the Arrowverse. So how will this next Arrowverse crossover, let alone the Batwoman series, explore Gotham City without introducing Batman?

Page 2 of 2: Knightfall Could Have Happened in the Arrowverse

Bane holding Batman over his head

Bane Could Have Broken the Bat in the Arrowverse

So far, we don't know much about the Batwoman TV series. All we have is the official synopsis, which doesn't suggest that Gotham City is well-protected anymore.

"In the series, Kate Kane, armed with a passion for social justice and a flair for speaking her mind, soars onto the streets of Gotham as Batwoman, an out lesbian and highly trained street fighter primed to snuff out the failing city’s criminal resurgence. But don’t call her a hero yet. In a city desperate for a savior, Kate must overcome her own demons before embracing the call to be Gotham’s symbol of hope."

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It's an exciting, comic-book-accurate take, but it most definitely hints that Batman is absent. Gotham is described as "a city desperate for a savior," with Kate Kane needing to overcome her own inner demons "before embracing the call to be Gotham's symbol of hope." The clear implication is that the criminals of Gotham are no longer being hunted down by the Dark Knight; Batman is gone, his symbolic role as defender of the city apparently vacated. Kate will embrace the Bat-symbol in order to become the hero and vigilante Batman used to be. Something has clearly happened to the Dark Knight.

The solution may well lie in one last Batman Easter egg, this time in Legends of Tomorrow. In the season 1 episode "Blood Ties," Rip Hunter gives a brief lecture about the benefit of being a Time Master. "I've seen darker days," he insisted. "I've seen Men of Steel die and Dark Knights fall." That comment seems to be a reference to famed comic arcs The Death of Superman (where Doomsday killed the Man of Steel before his convoluted return) and Knightfall, the story where Bane broke the Bat. An iconic 1993-1994 arc, Knightfall saw physical powerhouse and tactical strategist Bane wear down Batman, first orchestrating a mass breakout from Arkham Asylum before attacking a physically and emotionally exhausted Dark Knight. He broke Batman's back (a key part of the arc dramatized in The Dark Knight Rises), leading to a period where Bruce Wayne stepped back from Batman.

Rip Hunter's line seems to imply that, at some point, Knightfall has happened in the Arrowverse. of course, as he's is a time-traveler, it's impossible to say for certain when that would take place. It likely hadn't happened by Arrow season 6 given Oliver joked that Bruce Wayne could have left Gotham to act as a vigilante, but it could easily have happened since. Indeed, if the events of Knightfall happened in a similar way to the comics, it would explain why Gotham City is in chaos by the time of Batwoman: some of the most dangerous lunatics from Batman's rogues' gallery could still be free, wreaking havoc in Gotham.

It's worth noting that this comes mainly from circumstantial evidence, with the key motivator being a throwaway line, but it's definitely the most satisfying explanation as we head into Gotham proper.

Will Batman Ever Appear in the Arrowverse?

Heroes of Gotham City Robin Batman Catwoman Nightwing Superman Oracle Harvey Dent Commissioner Gordon Huntress

Batman's presence in the Arrowverse is implied by Batwoman, but that doesn't mean we're any closer to seeing him. Speaking at the Television Critics Association press tour in 2013, Kevin Reilly - Chairman of Entertainment at Fox - revealed that the network owned the entire franchise rights for Batman. That's why Batman hasn't already been introduced into the Arrowverse. Of course, the question mark is whether or not those rights will continue should Disney's proposed purchase of the bulk of Fox's TV and media empire go ahead. Some contracts do have clauses that mean rights revert in circumstances like this, but there's as yet no evidence this is the case for the Batman TV franchise.

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That doesn't mean Batman's rogues' gallery and secondary characters aren't available for use in Batwoman, though; Arrow's plans to use Harley Quinn suggests Fox don't have the exclusive rights to the Dark Knight's supporting characters and cast. In which case, the fact that Oracle has been name-dropped makes her a real possibility, while even villains like the Joker and Two-Face seem to already be established parts of the Gotham underworld. Classic Batman locations like Blackgate Penitentiary and even Arkham Asylum should be available to the Batwoman series as well.

It's true that, in the past, Warner Bros. has had real concerns about brand dilution; that's why Arrow's plans for Harley Quinn were canceled, after all. But that argument seems harder to maintain given that the studio currently has multiple Joker films in the works. It's possible that recent charges at Warner Bros. driven in part by the AT&T/Time Warner merger, have led to a change in approach here. If that's the case, the Batwoman TV series will have access to one of the greatest rogues' galleries in comic history, as well as classic supporting characters like Commissioner Gordon and Oracle.

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