WARNING: The following article contains spoilers for the series finale of Gotham, "The Beginning...," which aired Thursday on Fox.

Forget Henry Cavill's digitally removed facial hair in Justice League, DC fans have a new MustacheGate on their hands.

Gotham viewers have waited for years for Bruce Wayne to become Batman, for the Joker rise out of a vat of toxic chemicals, and for Jim Gordon to become a mustachioed police commissioner. In its final season, the Fox series finally delivered on all of those fronts. Well, almost.

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Yes, Ben McKenzie's Gordon was promoted to commissioner in Gotham's penultimate episode, but fans had to wait one more week for the character to sport his iconic facial hair. But there's a catch -- almost as soon as the mustache appears in "The Beginning ...," it disappears, never to be seen again.

Gotham Series Finale

Since McKenzie debuted as Jim Gordon in 2014, fans have wondered if he would ever boast the character-defining mustache. (The actor even tried out different mustaches in 2016, on Jimmy Kimmel Live!.) Gotham actually teased the facial hair once, when Gordon sported a thin mustache during a dream sequence in the Season 4 episode, "A Beautiful Darkness."

Because the series finale was already confirmed to take place 10 years in the future, it seemed all but certain that Gordon's look would finally become comic book-accurate. And it does, for a solid few minutes.

After the time jump that opens the episode, we find the older Gordon as a weary police commissioner, contemplating retirement, and he does so with his signature mustache. For a moment, like every other aspect of Gotham, it seem this too will line up with the comics. But that's not the case. A few minutes later, Gordon is back home, and his mustache is gone. He tells his wife Leslie that he tried something, and it didn't work ... and that's it. Gordon spends the rest of the hour clean-shaven.

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After years of teasing Gordon's mustache, Gotham ultimately paid it off for barely the length of an act. So while the episode features comics-accurate versions of Penguin, Riddler, Joker and Batman, alas, it stops short of finally committing to a fully mustachioed Gordon.

Gotham stars Ben McKenzie as James Gordon, Donal Logue as Harvey Bullock, David Mazouz as Bruce Wayne, Robin Lord Taylor as Penguin, Camren Bicondova as Selina Kyle, Erin Richards as Barbara Kean, Sean Pertwee as Alfred Pennyworth and Shane West as Bane. Season 5 and The Complete Series will be available June 11 on Blu-ray and DVD.