Marlene King working on ‘City of Bones’ screenplay
Marlene King, the mastermind behind the successful ABC Family series Pretty Little Liars, is working on the screenplay for City of Bones, the first installment of Cassandra Clare’s bestselling Mortal Instruments series.
King, who is head writer, executive producer and showrunner for PLL, shared the news with her Twitter followers Thursday night and Clare confirmed the news.
Having been the brain trust behind the Pretty Little Liars series, a Young Adult book series written by Sara Shepard that has been adapted to television, King knows the ins-and-outs of teenage angst, a more than relevant theme throughout the series.
And already she is smitten with the Mortal Instruments world.
Clare said that she is looking forward to seeing what King brings to The Mortal Instruments.
King even teased that she might share a few lines from the City of Bones script in a couple of days.
Clare recently revealed that one of the things holding up production of the film was that the script wasn’t finished yet. Now we know that King is the one working on it.
Who’s excited to see what King will bring to The Mortal Instruments movie?
TMI Source 
The screenwriter they hired was Jessica Postigo. I remember that she had completed the draft of the script. I think they had an issue with her or something didn’t work out so they hired Marlene. That’s probably why the script process is taking so long. They had to start all over again!
She only did a ‘polish’ on my script, she never re-did it.