Now, the trailer confirms that Nagini was once a circus performer who could turn herself into a huge snake for the delight of muggles. Nagini has been considered the only living thing he ever cared about, and knowing about her human side casts a totally different light on the relationship.
Rowling claimed on Twitter that she's been holding this secret for "around 20 years", and whether or not that's true it changes our entire perspective of Nagini the snake.
"She does feel sometimes it's not controllable". "She is bound to [permanently] transform at some point to a beast so she feels this pressure that the clock is ticking". "Credence is special to her because he encourages her to use her power".
The most notable element for Potter fans, however, is the presence of Nagini, played here by Claudia Kim.
So where she was just a force of pure evil before, The Crimes of Grindelwald is injecting some sympathy into this character whose beheading by Neville Longbottom we once cheered. And as its latest trailer makes clear, it'll show off quite a few new creatures for Newt to manage - not to mention that, as we learned on our set visit, it'll feature at least a couple of scenes at Hogwarts, which will no doubt please the Potterphile faithful. But there's something more troubling about this twist. Yes, we have a new woman of color in the universe of Harry Potter ... who is destined to lose control, turn into a serpent forever, and become the tool of one of the most powerful white wizards of all time? He turned her into a horcrux after killing Bertha Jorkins in Albania, shortly before the events of Goblet of Fire. Yeah, this may be an even worse retcon than making Dumbledore gay and refusing to follow up on it.
You'll also get glimpses of young Albus Dumbledore, or Youngledore as we like to call him, as well as a young Gellert Grindelwald as students.