Warning: There are spoilers ahead for "Fantastic Beasts: Crimes of Grindelwald."

A new trailer for "Fantastic Beasts: Crimes of Grindelwald" was released Tuesday and confirmed a longtime fan theory about Voldemort's snake, Nagini.

The serpent who acted as one of the Dark Lord's horcruxes was actually once a woman.

Early in the trailer, Credence (Ezra Miller) calls out to Nagini at a circus and we see actress Claudia Kim transform into the familiar snake.

Were you surprised by this reveal? Claudia Kim is Nagini. Warner Bros.

Many were floored at the initial revelation. Author JK Rowling said on Twitter it's a reveal she has been sitting on for about 20 years.

But soon afterward, fans started questioning the casting of an Asian actress in the role.

Many find it problematic that a woman of color is playing a cursed woman who eventually becomes a snake and slave to "Harry Potter" villain Voldemort.

—the handmaiden stan (@MlMAKIRIGOE) September 25, 2018

The Nagini casting is the latest "Fantastic Beasts" creative choice to upset fans.

Fans have been very vocal about their displeasure with Johnny Depp still being in the movie as the film's villain, Grindelwald. Depp's ex-wife Amber Heard accused the actor of domestic violence while the two were married. LGBTQ fans have also expressed their frustration with a perceived refusal to put an overtly gay version of Dumbledore on screen after Rowling said she "thought of Dumbledore as gay" after the final book's release.

"Fantastic Beasts: Crimes of Grindelwald" is in theaters November 16.

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