That time a book club tweeted J.K. Rowling and she crashed it for cake

If you ever want J.K. Rowling to attend your book club, all you got to do is bring the cake.

The Harry Potter author and screenwriter of the upcoming Fantastic Beasts and Where to Find Them surprised a tiny Scottish library when she showed up to their Saturday book club unannounced. Well, not entirely unannounced, as she had been tweeting the Orkney Library earlier that day about the club's discussion of her book The Cuckoo's Calling, which she published under the pseudonym Robert Galbraith.

Rowling has a regular presence on Twitter, so Stewart Bain, an assistant at the library in Orkney according to the BBC, thought nothing of her reply to their invitation. So he decided to have a little more fun by offering her cake.

It turns out "lemon cake" were the magic words, because to everyone's surprise, Rowling -- who probably needed a nice break from writing her Pottermore stories -- showed up. According to the BBC, Rowling booked a plane to Orkney just for the event. She snapped a photo with the library staff, got a special tour and later thanked them on Twitter.

There you have it folks -- if you ever want to "Accio" Rowling, you just have to offer her lemon cake.

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