From J.K. Rowling’s official website today:
Warner Bros. announced on 12th September 2013 that J.K. Rowling would be making her screenwriting debut with Fantastic Beasts and Where to Find Them, the first in a new film series which is part of their expanded creative partnership with J.K. Rowling. The films will be inspired by Harry Potter’s Hogwarts textbook of the same name, and will feature the book’s fictitious author, Newt Scamander.
“It all started when Warner Bros. came to me with the suggestion of turning Fantastic Beasts and Where to Find Them into a film. I thought it was a fun idea, but the idea of seeing Newt Scamander, the supposed author of Fantastic Beasts, realized by another writer was difficult. Having lived for so long in my fictional universe, I feel very protective of it and I already knew a lot about Newt. As hard-core Harry Potter fans will know, I liked him so much that I even married his grandson, Rolf, to one of my favourite characters from the Harry Potter series, Luna Lovegood.
As I considered Warners’ proposal, an idea took shape that I couldn’t dislodge. That is how I ended up pitching my own idea for a film to Warner Bros.
Although it will be set in the worldwide community of witches and wizards where I was so happy for seventeen years, Fantastic Beasts and Where to Find Them is neither a prequel nor a sequel to the Harry Potter series, but an extension of the wizarding world. The laws and customs of the hidden magical society will be familiar to anyone who has read the Harry Potter books or seen the films, but Newt’s story will start in New York, seventy years before Harry’s gets underway.
I particularly want to thank Kevin Tsujihara of Warner Bros. for his support in this project, which would not have happened without him. I always said that I would only revisit the wizarding world if I had an idea that I was really excited about and this is it.”