Cassandra Clare recently talked with EW about the process of adapting The Mortal Instruments: City of Bones into a film.

When asked about the process of adapting the book to film, Clare says that her opinions were taken into consideration during the making of the movie. Clare stated, “A book is really a one-person project, and a movie is a multiple-person project. So they’ve let me be a voice in the room, which I really appreciated, but mine is not the only voice.” For most book lovers, it is exciting to hear that the author was involved in the process of adapting the novel, as it assures to some extent the heart of the novel will remain intact.

When discussing her favorite casting choices, Clare says they were Jared Harris as Hodge Starkweather and Robert Sheehan, who plays Simon. When discussing Robert Sheehan, Clare says he’s not as well-known here in the U.S. as he is in the U.K. She first encountered him when she was in the U.K. and a friend of hers showed her his show Misfits. He’s an amazing comic actor and so funny.

As far as other Clare’s others projects go, the next book released will be the highly anticipated final book in The Infernal Devices series, Clockwork Princess. The final book in the The Mortal Instruments series, City of Heavenly Fire, doesn’t release until 2014.

To hold you over, The Mortal Instruments: City of Bones trailer will be premiering this Thursday on MTV. To read more of the interview with Cassandra Clare, check out EW’s Shelf Life.