The Wizarding World has grown by leaps and bounds since J.K. Rowling first dropped Harry Potter and the Sorcerer’s Stone, and Fantastic Beasts: The Crimes of Grindelwald contributes even more to the Potterverse. The Fantastic Beasts films, starting with the first in the franchise, Fantastic Beasts and Where to Find Them, take place long before Harry Potter arrives on the scene. However, they include numerous references to future Potter plot points.
The Harry Potter connections in Fantastic Beasts 2 are not just Easter eggs; they actually re-contextualize many events in the Harry Potter series. Aside from referencing previous films, Fantastic Beasts 2 expands the overall mythos of the series. A lot of the following details are for fans who’ve kept up with the series since its inception, but that doesn’t mean first-years won’t enjoy this guide to the connections between Fantastic Beasts 2 and the rest of the Harry Potter series.
Polyjuice potion makes a big comeback in the second installment of Fantastic Beasts, and it turns out that even the famed Newt Scamander can't get the temperamental potion to stick. Before popping into the Parisian Ministry of Magic to get information on Credence, Newt takes a swig of polyjuice potion so he can take the form of his brother.
Unfortunately, he immediately runs into the person he's impersonating, so it's all for naught. His problems are compounded when the potion wears off almost immediately.
Nagini, the giant snake belonging to He Who Must Not Be Named, began her life as a Maledictus - a human female born with a blood curse that causes her to permanently turn into a creature. The audience sees her in human form in Fantastic Beasts 2 when she appears as a member of a traveling sideshow. Credence, who is in love with the snake woman, helps her escape the circus.
She sticks with Newt's crew at the end of the film, so it'll be interesting to see how she ends up around Voldemort's neck.
Blink and you'll miss it, but when the sideshow leaves Paris, an elf traveling with the circus uses something resembling a Deluminator to put out some of the street lights.
Maybe he and Dumbledore shop at the same spots in Diagon Alley.
Forget everything you know about the timeline of the Wizarding World. While fans previously placed Minerva McGonagall's birth in 1935, it appears as though she was already teaching at Hogwarts in 1927. The audience only gets a quick glance at the teacher first portrayed by Maggie Smith, but you do hear the character's name multiple times.
First, Dumbledore tells his students to "go with Professor McGonagall" when Aurors interrupt his dueling club, and her name is heard again in Leta Lestrange's flashback. Is it the same McGonagall in an altered timeline? Is it her mother? Or has the professor used a time-turner?