He rang me up and said, Look, Im spinning plates here.

I really need to understand what Snapes up to?

Am I a pure baddie?

Alan Rickman and J.K. Rowling

Alan Rickman with J.K. Rowling in 2013.David M. Benett/Getty Images

He was the only person I told: You were in love with Harrys mother.

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I talked him through it: You are a double agent.

But you do dislike Harry.

John Lithgow

You cant overcome your quite visceral dislike of this boy who looks just like your arch enemy.

So I told Alan Rickman what was coming, way before it came in the movies.

Killing Snape was awful.

I always knew he was going to go.

I couldnt bear killing Lupin and Tonks [Harrys teacher and his wife], that was so sad.

Oh and Fred [Weasley].

She is the bestselling author in the world, with reported sales of 600million books.