JK Rowling knows exactly who she wants to play young Dumbledore

Speaking at the premiere of Fantastic Beasts and Where to Find Them, the author revealed that she already had an actor in mind for the part – but she won't tell anyone who it is.

On casting the future Hogwarts headmaster when he pops up in the Fantastic Beasts sequel, Rowling told E! News: "I have, of course, thought about this. I do have a name.

"I do have someone in mind, but I can't say it. Because if that person doesn't get cast, then the person who does get cast will blame me forever for having said it, won't they?

"So, I'm going to just keep quiet."

"If it is that person," she teased, "then you will know about it."

Rowling has previously revealed that Dumbledore is gay, but with rumours swirling about the nature of his relationship with dark wizard Gellert Grindelwald (Johnny Depp), the Harry Potter creator remained coy.

"Well, I can’t tell you everything I would like to say because this is obviously a five-part story, so there’s lots to unpack in that relationship," she told Screencrush.

"I will say that you will see Dumbledore as a younger man, and quite a troubled man because he wasn’t always the sage. He was always very clever, but we’ll see what I think was the formative period of his life.

"As far as his sexuality is concerned, watch this space."

Fantastic Beasts and Where to Find Them is released in the UK on 18th November