Arrowverse "Elseworlds" Crossover Reveals First Arkham Asylum Easter Egg

Arrow co-creator Marc Guggenheim has revealed the first Arkham Asylum Easter Egg in this year’s [...]

Arrow co-creator Marc Guggenheim has revealed the first Arkham Asylum Easter Egg in this year's Arrowverse crossover.

Guggenheim shared to Twitter a photo of a cell door with "Guggenheim, M." written on the inmate nameplate. This is obviously an homage to Guggenheim. Guggenheim seems to wonder what it reveals about how producer James Bamford thinks of him.

"I've encouraged a lot of Easter Eggs in this year's crossover, but this might be going too far," Guggenheim tweeted. Take a look below.

Arkham Asylum is the famous, or infamous, home for the criminally insane in Gotham City, where most of Batman's villains spend most of their downtime. Gotham will make its first appearance in the Arrowverse as part of this year's "Elseworlds" crossover between Arrow, The Flash, and Supergirl. The crossover will feature the debut of Ruby Rose as Batwoman, Gotham City vigilante and member of the Batman Family. DC Entertainment and The CW has already revealed the first look at Rose in her full Batwoman costume.

"I get to be Batwoman," Rose told Jimmy Fallon during an episode of The Tonight Show. "I feel like the reason I kept getting so emotional was because, growing up watching TV, I never saw someone on TV that I could identify with, let alone a superhero. [Tearing up] I said I wouldn't do that and I've always had this saying, well not me, Oscar Wilde, which is 'be yourself because everyone else is taken' and so I always lived by that motto and the second motto when I came into the industry was 'be the person that you needed when you were younger' and I feel like one motto sort of led me to the other and I just kept crying about it."

"Elseworlds" finds Green Arrow (Stephen Amell), The Flash (Grant Gustin), and Supergirl (Melissa Benoist) heading to Gotham City and teaming up with Batwoman after the mad science taking place within Arkham Asylum draws the attention of heroes from across the multiverse.

Photos from the "Elseworlds" crossover also revealed that fans will see Superman's black suit, Stephen Amell and Grant Gustin swapping superhero roles, and John Wesley Shipp suiting back up as the Flash, a role he played in the 1990s The Flash television series.

Are you excited to see Arkham Asylum on The CW? Let us know in the comments!

The Arrowverse crossover, "Elseworlds", will take place across three nights, kicking off on Sunday, December 9th on The Flash at 8 p.m. ET. It continues on Arrow Monday, December 10th at 8 p.m. and then finishes up on Supergirl Tuesday, December 11th at 8 p.m. ET.