It has begun.

That’s right…the official cast announcements for the upcoming Mortal Instruments film, based on the ever-popular series by Cassandra Clare!

And in an unexpected—but not unwelcome—twist on Hollywood protocol, the author herself has been given the go-ahead to break the news of who’s playing whom, posting her impressions of new casting decisions on her blog for all her devoted followers to read.

And her first big newsbreak?  The part of Isabelle Lightwood, who will be played by The Borgias alumnus, Jemima West.

Cassandra Clare had only good things to say about the casting, complimenting Ms. West on her looks and tough attitude during auditions.  The author also gives us tantalizing hints as to the casting of Izzy’s twin, Alec, and promises to make the big reveal in a subsequent post…that we are still waiting for.  But according to what has been revealed so far, Alec will be played by a British actor who is better known.

Does not even remotely narrow the field, but…anyone have any ideas who it could be?

Leave your thoughts in the comments!