A new casting announcement for this season's Arrowverse crossover reveals the heroes of The CW will pay a visit to Gotham City.

Lost and Justified veteran Jeremy Davies will play Dr. John Deegan, a doctor at the notorious Arkham Asylum for the Criminally Insane, whose machinations draw Green Arrow, The Flash and Supergirl to Gotham.

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Although Gotham, the traditional stomping grounds of Batman, has been referenced on Arrow, DC's Legends of Tomorrow and Supergirl, this will be the first time it's actually shown on the Arrowverse dramas. Fans are still left to wonder whether this is the Gotham on Earth One, home of Green Arrow and The Flash, or Earth-38, inhabited by Supergirl.

Jeremy Davies in Sleepy Hollow

While the introduction in the crossover of Batwoman, played by Ruby Rose, led to speculation that Gotham might finally make its debut -- the city is even referenced in the character description -- this is the first confirmation.

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Davies, who won an Emmy Award for his portrayal of Dickie Bennett on FX's Justified, was a series regular on Fox's Sleepy Hollow, and had a recurring role on NBC's Hannibal. He's also widely known for his performance as Daniel Faraday on ABC's Lost.

The addition of Davies follows the casting last week of Grimm star Elizabeth Tulloch as Lois Lane, who will appear in the crossover alongside Tyler Hoechlin, who reprises his role as Superman.

The three-night Arrowverse crossover begins Sunday, Dec. 9, at 8 p.m. ET/PT on The CW.