Butch Gilzean will emerge from Slaughter Swamp next week on Gotham a changed man, transformed in the classic DC Comics villain Solomon Grundy. We get our first glimpse of his new form in the promo for the Oct. 19 episode "There's No Coming Back From This."

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Some fans have been awaiting his debut since the Season 3 finale when the mercurial henchman (played by Drew Powell) was shot in the head by his boss Barbara Kean. Left in a vegetative state, Butch was hospitalized in the episode's final moments, where his real name was revealed as Cyrus Gold, recognized by longtime DC Comics fans as the original identity of Solomon Grundy.

Dumped into the swamp's murky waters by unscrupulous hospital administrators and left for dead, Butch/Cyrus instead becomes a hulking undead monster. In that new form, his first interaction will be with none other than Edward Nygma, aka The Riddler.

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“We begin the story of a very unlikely friendship between these two who are sworn enemies but now, all of a sudden in Season 4, are best friends as they move through Gotham,” explained executive producer John Stephens.

Airing Thursdays at 8 p.m. ET/PT on Fox, Gotham stars Ben McKenzie as James Gordon, Donal Logue as Harvey Bullock, David Mazouz as Bruce Wayne, Robin Lord Taylor as Penguin, Cameron Bicondova as Selina Kyle, Erin Richards as Barbara Kean and Sean Pertwee as Alfred Pennyworth.