In the trailer, Dumbledore glances into the magical artifact - which the future Hogwarts headmaster once described as showing "nothing more or less than the deepest, most desperate desire of our hearts" - and sees. his former friend and schoolboy crush, Grindelwald.
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. Keep your eyes peeled while watching as it is a pretty brief shot, which shows both characters touching the Mirror of Erised.
Fantastic Beasts and The Crimes of Grindelwald features Eddie Redmayne, Katherine Waterston, Dan Fogler, Alison Sudol, Ezra Miller, Zoë Kravitz, Callum Turner, Claudia Kim, William Nadylam, Kevin Guthrie, Carmen Ejogo, Poppy Corby-Tuech, with Jude Law and Johnny Depp.
Are you going to see this film when it releases?
Warner Bros. dropped the final Fantastic Beasts sequel trailer on Tuesday, revealing the footage on Twitter and broadcasting live fan reactions on electronic billboards in New York City, Toronto, and Tokyo (via Variety).
Meanwhile, Newt's handsome brother Theseus (a confirmed Hufflepuff!) is ready to fight Grindelwald under ministry orders, but those cute magical beasts are the real scene-stealers of this movie. However, even with the story being set in the same universe, The Crimes of Grindelwald is itself a unique story, something that the cast and crew have already begun to tease.
Harry Potter fans will instantly recognize this as the name of Lord Voldemort's snake, which the Dark wizard later uses as a Horcrux to preserve part of his soul in his efforts to gain immortality.
Essentially, Nagini is a ticking time bomb of tragedy who will eventually transform into a snake permanently, and perhaps lose all memory of humanity. "She wants to stay a human being and I think that's a wonderful contrast to the character".
Elsewhere in the trailer, we also see Nagini, a human with cursed blood who has the ability to transform into a snake - and who in later years belonged to Lord Voldemort and was his final horcrux to be killed; she was killed by Neville Longbottom with Godric Gryffindor's Sword.