Old-school Batman fans may be in for quite the nice surprise during this year's ArrowVerse crossover, as a new set photo reveals Michael Keaton's Bruce Wayne from Tim Burton's Batman will be part of the ambitious superhero festivities. While we may not see Keaton in the flesh, at the very least, his version of the billionaire turned vigilante crime-fighter will be referenced during the event. Beyond that, more questions than answers currently exist.

Recently, a photo from the set of Crisis on Infinite Earths, which is currently filming, began circulating on social media. It features a copy of the newspaper the Gotham City Gazette and, on the cover, we see Michael Keaton's Bruce Wayne. The headline reads, "WayneTech CEO Bruce Wayne to Marry Socialite Selina Kyle." That headline has other implications, as Selina Kyle, the person under Catwoman's mask, is also referenced here. In the Tim Burton Batman universe, Kyle was played by Michelle Pfeiffer in Batman Returns.

RELATED: The Flash Season 7 Casts Jordan Fisher as Bart Allen

Crisis on Infinite Earths is one of the most famous crossover events in DC Comics history and adapting it for TV offers ample opportunity to revisit DC history, as it spans the entirety of the multiverse. First published in 1985, the story was written by the Marv Wolfman and illustrated by George Perez. The story sees a villain named Anti-Monitor, the reverse of The Monitor, who seeks to destroy all life across the multiverse. His journey brings him up against many of DC's most famous heroes, Batman included. The event is also remembered for including the deaths of both The Flash and Supergirl. But the main point is different versions of popular characters can be introduced, thanks to the multiverse angle.

Even if Michael Keaton just appears in the page, it adds to an already stacked cast of guest stars. This year's ArrowVerse crossover also sees Smallville's Tom Welling, Supergirl's Tyler Hoechlin and Superman Returns actor Brandon Routh all playing Clark Kent/Superman. Routh will also appear as Ray Palmer/The Atom. Other guest stars include LaMonica Garrett (Anti-Monitor), Jon Cryer (Lex Luthor), Elizabeth Tulloch (Lois Lane), Erica Durance (Lois Lane), Kevin Conroy (Bruce Wayne/Batman), Johnathon Schaech (Jonah Hex) and Ashley Scott Will (Huntress). Batman '66 star Burt Ward will also appear in an undisclosed role, though it's expected he'll be reprising his role as Robin, the Boy Wonder.

This year's crossover will span Arrow, The Flash, Supergirl, Legends of Tomorrow and Batwoman. The Legends of Tomorrow sat our for last year's Elseworlds and Batwoman recently debuted. Adding them into the mix makes this the network's largest crossover event ever. Cress Williams will also make his first official ArrowVerse appearance as Black Lightning. Crisis on Infinite Earths kicks off with Supergirl on The CW on Sunday, December 8. Be sure to check out the set photo teasing Michael Keaton's Bruce Wayne for yourself below.