Fantastic Beasts and Where to find them had it's dark moments and themes - but for the most part it was a light movie, and while it had its dark moments it was fun. The Crimes of Gridelwald on the other hand is mostly dark and full of dark themes - child abuse, brainwashing, infanticide - make no mistake, while there are a few scenes that happen in Hogwarts it's not the fun filled school you see in any of the Potter movies. No spoilers but I think they made an inspired choice in casting Jude Law as Dumbledore.