Supernatural star Jensen Ackles paid a visit to the set of the Arrowverse's upcoming "Elseworlds" crossover, and Arrow star Stephen Amell immediately squashed the beginnings of any rumor that the actor might be joining the Arrowverse.

"Let me squash this rumor right now," Amell wrote on Twitter. "@JensenAckles was on set tonight because he’s Grant Gustin’s #2 fan (I’m #1) and not because he’s playing The Batman."

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Amell posted the picture following a photo of Ackles reportedly on set of the crossover was posted by user scoobykoo on Instagram. The small screen's Oliver Queen previously teased a secret cast member for "Elseworlds," but Ackles won't be that person.

Although many details about the upcoming crossover are unknown, a number of actors are set to make their Arrowverse debuts, including Ruby Rose as Batwoman/Kate Kane and Elizabeth Tulloch as Lois Lane. Tyler Hoechlin will reprise his role as Superman and don the character's black suit. A poster for the event also revealed Amell wearing the Flash's outfit and Grant Gustin, who plays the Scarlet Speedster, dressed up like the Green Arrow.

In addition to his role as Dean Winchester in Supernatural, Ackles voiced the character of Jason Todd/Red Hood in the acclaimed 2010 DC animated movie Batman: Under the Red Hood.

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“Elseworlds," this year’s Arrowverse crossover event, will begin with The Flash on Sunday, Dec. 9 at 8 pm ET, continue with Arrow on Monday, Dec. 10 at 8 pm ET and end with Supergirl on Tuesday, Dec. 11 at 8 pm ET.