Not all is "fantastic" in Potter world after the newest trailer for Fantastic Beasts: The Crimes of Grindelwald dropped this week.

The casting of South Korean actress Claudia Kim as Nagini, a snake who serves as a slave to villain Voldemort, in the final trailer for the film out in November, doesn't have everyone under its spell.

Fans of the series have described the casting of an Asian actress in the role as "offensive" and "inappropriate", saying it plays into stereotypes of Asian women as "submissive".

They also criticised the filmmakers' attempt to introduce diversity to the largely white cast by "retroactively" reimaging the "problematic" character.