Sorry in advance for the wall of text, and spoilers ahead.
Not great. Pretty bad, actually. As my mother has said about each film in the Fantastic Beasts series, it feels like there was a book you were supposed to read first that made more sense. This one was a cacophony of plot events and disjointed scenes, strung together by the occasional burst of John Williams’ original themes/motifs to remind you what you were meant to be watching. Eddie Redmayne continues to do a great job of playing a person with debilitating Asperger’s or some other disorder, making it very hard for the general audience to connect with him on any level. Tina’s been given the boot, for the most part; probably because someone pointed out to Rowling that her stories are still overwhelmingly white, and subsequently we get “Lally?” who is a nightmare of silly accents and annoying dialogue. Mads Mikkelsen, unsurprisingly, does a better job as Grindelwald than Depp did, and frankly should have been cast in the first place. As always, Jacob Kowalski is a treat to watch and should have been the main character from the get-go. Why they gave him a stick is beyond me, though—it wasn’t a wand, it didn’t fool anyone that it was, and it didn’t seem to serve any purpose. The plot hinges on yet another shoehorned “fantastic beast” that really seems to be stretching the imagination, one that can pick the right leader for the wizarding world (which I was unaware as to having an overall leader)? All plot threads from the previous film are unceremoniously undone—Credence, revealed as Aurielius Dumbledore at the end of Crimes is actually Aberforth’s son, and is dying so as to not burden the audience or Warner Bros. with any more Ezra Miller. Queenie, ensnared by the silver-tongued promises of freedom to marry whomever she likes by Grindlewald at the end of Crimes does essentially an immediate about-face, and sees no consequences. The law has also, if you’ll pardon the pun, magically changed between the first film and this one to allow her to marry Jacob, a Muggle. The blood-pact? Blood-bond? Mysterious silly macguffin that kept Dumbledore and Grindlewald from facing each other directly? Is, again, magically removed as an obstacle with no real explanation as to how or why, presumably so they can wrap this series up quick in the next one.
These films have been frankly messy and rather disappointing. Had they chosen a proper direction to go—any one direction, really—they could have been…well, probably not great, but good. Had they just done Fantastic Beasts—the interesting and strange journeys of a magizoologist exploring the wizarding world and discovering new and wondrous creatures, with some light action and comedy and romance, could have been good. A serious, dramatic exploration of Grindlewald’s rise to power, mirroring that of Hitler’s in the 20s and 30s, culminating in a world war for both Muggles and magic alike, could have been good. But pairing them both together, along with about forty other subplots and mysteries and cameos and Easter eggs, leaves these films bloated as well as watered-down.
To echo some of the sentiments above, sometimes the ignoring of social injustices of the past damages the series greatly, I think. As an example, in the first film, Rowling wants to portray the wizarding world as so much more progressive and enlightened—and so 1920s wizarding America has a female president. Can’t marry who you like, though, and they have a gruesome form of capital punishment with no trial system, but hey, progressive that a woman of color is their leader! Same goes for the other films in this series. They ignore real-world problems that would fit quite nicely into the plot if executed well, and end up falling flat as competing ideas kill each other. Why wasn’t there more overt parallels drawn to the Nazis within the wizarding world? Can there be Jewish witches and wizards? Is that a thing? How would they fare under Muggle Nazi fascism? We’ll never know. Too interesting of ideas.
Overall, these films have had moments of charm, but nothing on the scale of the first three Harry Potter films. They’re slightly better than 4 and 5 on a technical level but the lack of a strong underpinning story and characters means even the two worst (in my opinion) Harry Potter films win out over Fantastic Beasts. This one was long, and I shudder to think that two more will follow. If they were handed over to a filmmaker with a distinct style and vision, as happened with Alfonso Cuaron for Prisoner of Azkaban, I’ll be interested in returning. But otherwise, dull times are ahead.