Flo Lieb’s review published on Letterboxd :
When it comes to unnecessary spin-offs which are extended into a film franchise this one surely qualifies and yet is above and beyond crap like those Hobbit movies. A wonderful period setting breathes some "fresh" air into the Potterverse, adding some dark themes (murder, child abuse) to this former kids' series.
Still, Fantastic Beasts and Where to Find Them is not a very good film. Most of all this movie lacks characters. It has a lot of protagonists, sure, but none of them are fleshed out like Harry, Ron, Hermione, Draco, Snape et al where back in the first Potter film. Newt is kind of a shy nerd with some hinted back story that seems big on drama. There is a former friend and love interest which turned her back on him and he also got expelled yet seems extremely handy at magic. He runs into suspended auror Tina who once investigated some anti-witch cult but the film never really gets into the specifics or the resolution of this investigation.
Whereas one part of the story revolves around Newt and his band of new acquaintances trying to get a handful of the titular fantastic beasts back into his magical zootopian briefcase after they've escaped (a light and humorous adventure), the second narrative concerns itself with some dark prodigy child and terroristic attacks by Gellert Grindelwald, both investigated by an U.S. auror played by Colin Farrell. Half mimicking the Voldemort threat from the Potter films and mashing it up with some Carrie undertones both storylines have a hard time co-existing, let alone being intertwined later on.
But most of it is in good fun and despite running probably 15-20 minutes too long for its own sake Fantastic Beasts and Where to Find Them offers an interesting and fresh look into a fantastical universe, alluding to offer more than we have seen so far.