It's official: the Dark Knight and the Emerald Archer co-exist in the same universe.

After years of sly nods, veiled references and generally dancing around the issue, Arrow finally confirmed that Batman (or at least his alter-ego) exists in the established DC TV universe, with Oliver Queen (Stephen Amell) name-dropping Bruce Wayne in the latest episode.

This content is imported from Twitter. You may be able to find the same content in another format, or you may be able to find more information, at their web site. Mayor by day. Hero by night. Stream the #Arrow premiere before tomorrow's new episode on The CW: https://t.co/zCi32rKGdv pic.twitter.com/2cEQUQbTFk — Arrow (@CW_Arrow) October 18, 2017

With his secret identity compromised after a photo showing him unmasked was leaked, Queen did his best in last Thursday's outing 'Tribute' to quash the suspicions of the press.

"Photos can be doctored. They could have put Bruce Wayne's head on that body," Olly insisted. "Has Bruce Wayne left Gotham to hang out in Star City recently? No!"

Fans went nuts – and who can blame them?

This content is imported from Twitter. You may be able to find the same content in another format, or you may be able to find more information, at their web site. Not going to lie, that Bruce Wayne Arrow reference was really cool and established Bruce and Gotham in the Arrowverse. Super cool. — ⚡️ (@TTFMike) October 21, 2017

This content is imported from Twitter. You may be able to find the same content in another format, or you may be able to find more information, at their web site. Supergirl and Arrow have now referenced Batman and Bruce Wayne.....now let’s get a CW Batman! — 𝕄𝕒𝕥𝕥 🙏🏽 (@_MrMattWhelan_) October 18, 2017

But was this reference just another fun tip of the hat, or was it – as many fans are now hoping – a tip-off that the Caped Crusader could be taking a trip to Star City?

The hard and disappointing truth is that it's probably just the former. For years, the brains behind Arrow – and its sister shows The Flash, Supergirl and Legends of Tomorrow – have been insisting that a Batman cameo is at best a long shot, at worst a total pipe-dream.

It's been a topic of conversation since before Arrow even launched – in August 2012, two months before the show's October premiere, executive producer Marc Guggenheim revealed his hopes of a crossover, though admitted such a decision was "above [his] pay grade".

Indeed, a few months later, Mark Pedowitz – president of The CW, which airs Arrow and its ilk – stated definitively that Batman was not "going to make a trip" to Olivier Queen's home city.

Sky

By 2015, Arrow was an established hit, having just kicked off its fourth season, but little had changed. "I love Batman," Guggenheim said. "He's probably my favorite DC character and of course I'd love to see him on Arrow, but that's just not in the cards anytime soon."

Greg Berlanti, another key creative figure in the Arrowverse, was still insisting as of August 2016 that there'd be no guest spots from Batman or associated characters (Nightwing, Batgirl et al) in any of the four shows he'd helped put on the air.

But why not? What are the obstacles standing in the way of this most fan-pleasing of crossovers? Well, for the longest time, one big problem appeared to be the big screen.

Though there's never been a clear and official statement on the matter, there have been plenty of rumblings in the past few years suggesting that DC's cinematic operation can have a significant – and often detrimental – impact on its TV output.

For DC and Warner Bros, it always seemed that the movies took precedence – going right back to 2000, when what would become Batman Begins scotched plans for a series about a young Bruce Wayne, leading to the invention of Smallville instead.

Warner Bros.

Last year, Arrow star Willa Holland alleged that the show was forced to kill off its own version of the Suicide Squad when DC and Warner Bros announced its plans for a feature based around the anti-hero team.

And, back in 2014, executive producer Andrew Kreisberg appeared to confirm that Arrow and The Flash – the two shows on the air at the time – were outright banned from featuring material relating to Batman or Superman: "There are things we can do, and there are things we can't. You won't be hearing 'Gotham' or 'Metropolis' on the show anytime soon."

But this stance had apparently softened a little by 2016, with Supergirl being permitted to introduce its own version of Superman (played by Tyler Hoechlin) – distinct from the contemporaneous movie version (played by Henry Cavill).

"We asked if we could have Superman in the first episode, and DC and Warner Brothers said we could have him for the first two episodes!" Kreisberg explained. "[It sounds] like we're abused kids. But we're so happy with what we get to do."

The CW

However fractious that relationship might be, DC / Warner Bros were happy to sign off on Superman appearing as a guest character on Supergirl, and so presumably wouldn't object to a Dark Knight guest spot on Arrow purely on the grounds of Batfleck's existence. So the movies aren't the thing.

Far more considerable an obstacle is Gotham, the FOX series charting the rise of the city's most demented villains, and – like that planned '00s series – featuring a young Bruce Wayne (David Mazouz) on his path to becoming its shadowy protector.

A crossover between two shows on two different networks would be a nightmare to negotiate – the character of John Constantine (Matt Ryan) might've jumped over to Arrow, but only once his solo series had been axed and was no longer a going concern for NBC.

Jeff Neumann/FOX

But even if FOX and The CW were able to navigate this legal and logistical minefield, the story and setting of Gotham exists outside the universe inhabited by Oliver Queen and company. Carrying a young Bruce Wayne over into the Arrowverse – with its established, adult versions of DC heroes – would not be an easy fit.

The only other alternative would be to introduce a third screen Batman, played by an entirely new actor... but surely that way madness lies?

Bruce Wayne getting name-checked on Arrow actually provoked a response from the official Gotham Twitter last week, and while the response could be seen as just playful banter, it's also pretty telling...

This content is imported from Twitter. You may be able to find the same content in another format, or you may be able to find more information, at their web site. Bruce Wayne was still in #Gotham last time we checked. 🦇 https://t.co/gK0PIgYAZR — Gotham (@Gotham) October 18, 2017

...because Gotham, we suspect, is where he'll stay.

Two different versions of a character in two different mediums – film and TV – is one thing. But two different Batmen on television, simultaneously?

DC might now be playing fast and loose with continuity and internal consistency, but even by their standards, we reckon that'd be a stretch too far. The fun Easter Eggs and nods to fans might keep on coming, but the fan dream of Green Arrow and Batman fighting side-by-side is, sad to say, likely to remain just that.

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