[Photo provided to China Daily]

British actor Law, who has received two Oscar nominations, has taken the torch from Richard Harris and Michael Gambon, who respectively played Dumbledore in the first two and remaining six Harry Potter films.

"It's really a wonderful and unique experience to take on a character who has already been played in his older years in such an iconic way," Law says.

A trailer for Fantastic Beasts 2 has sparked online discussions since one sequence shows Dumbledore gazing into the Mirror of Erised－the fictional device that reflects the deepest desires of those who look at it－and sees Grindelwald.

Law says he can't reveal this core part of the plot.

But he explains that viewers who watch a couple of more Fantastic Beasts films will discover the two are friends in their youth who are torn apart by events.