Tonight on Arrow (The CW, 8/7c), the Arrowverse finally sets foot in the infamous Gotham, after so many years of merely alluding to the gritty metropolis and its resident caped crusader. In fact, there was a time when you couldn’t even speak of Gotham if you were a superhero series.

Caroline Dries, who wrote Part 2 of the “Elseworlds” crossover event with Arrow EP Marc Guggenheim, years ago worked on Smallville — as did Flash showrunner Todd Helbing. And back then, she shared at a recent press event, “DC doesn’t let you say Batman or have anything about Gotham — like it’s just off-limits.”

Nowadays, though, especially ever since Gotham became its own TV series (over on Fox), “all of a sudden, we can do stuff,” Dries noted. “And for a bunch of geeks like us, you’re in Heaven. It’s [then just a matter of] trying to figure out what you want to use.”

Perhaps most memorably, Arrow‘s Oliver jokingly named Bruce Wayne as the Green Arrow’s possible true identity, but there have been multiple other nods. Said Helbing, “It reminds me of… this SNL skit where for the first time they could say a word and they did one skit where they said that word the whole skit.”

Compared to the worlds that Arrow, The Flash and Supergirl live in, the Gotham we see on Monday night has “a darker vibe,” Dries said. “We were trying to create, with music and the exteriors and the alleys and the grime, a sort of uncomfortable city.”

There was also a point made to give the Arrowverse’s Gotham a look that is distinct from the one on the Fox series. Shooting exteriors on location in the Windy City (versus good ol’ Vancouver), “We loved the idea of Chicago, because it feels like that’s the cityscape we’re looking for,” Dries explained. “It’s hard to do a new version of Gotham, but we knew the Vancouver skyline wasn’t quite right. It was a little too modern.”

Whilst in Gotham, Oliver & Co. will encounter Kate Kane aka Batwoman, played by Orange Is the New Black‘s Ruby Rose (who in success may headline her own CW series about the LGBT vigilante). “Ruby has a really strong, silent presence — her look is so powerful that you don’t want to take her eyes off of her,” Dries said. “She brings so much to the plate, we realized, just standing there and absorbing what the other guys are talking about. One of my favorite moments was when they show up at Wayne Enterprises and they’re all kind of bickering about Batman and she’s just standing there waiting for them to figure out this stuff. I didn’t know how working with her would be on the day, but that was a fun surprise.”

Alas, while Gotham is no longer a six-letter four-letter word for the Arrowverse, and Batwoman is fair game, Arrowverse viewers might not ever lay eyes on you-know-who. Batman.

“That’s the one where they cut you off!” Dries reported with a laugh. “Slowly but surely, we’ll just keep kicking away at it.”

That said, Batman is mentioned in Part 2, to some comedic effect.

Citing one of her favorite scenes — in which Oliver scoffs at the Dark Knight’s existence — Arrow showrunner Beth Schwartz said, “We introduce him as being the first vigilante, so it was kind of like poking fun at that a little bit and [Oliver] being defensive. He was the first Batman in his eyes, and so that was really fun, especially [Stephen] playing off of Grant [Gustin]… the two of them were so fun in this. I remember watching the cut and I was just cracking up.”

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