'Pretty Little Liars' Scribe I. Marlene King Reveals Her Favorite 'Mortal Instruments' Scene

When the news broke earlier this month that "Pretty Little Liars" executive producer and writer I. Marlene King would pen the script for the big-screen adaptation of "The Mortal Instruments," we nearly fell into a state only an anti-hyperventilation rune could cure. Translation: WE WERE SUPER EXCITED. After all, no one does teen better than Marlene. So when we called up the showrunner today to talk about the upcoming "Pretty Little Liars" Halloween special, you better believe we snuck in a few "Mortal Instruments" queries. Read what Marlene had to say about her favorite scene, working with author Cassandra Clare and keeping track of all that mythology after the jump!

Hollywood Crush: We must talk "Mortal Instruments" for a moment. How did you get involved with the project?

I. Marlene King: I had worked with one of the producers of the movie several years ago, and I did something that was action-oriented for that company, and he just thought of me right away. It's teen girl sensibilities but with all this great action and mythology. I read the first few books, and I was immediately throw into this world.

How far along are you in the script-writing process?

I'm rewriting a script that they had—Sony is now involved with the movie so there was already a script and now I'm rewriting it, and I'm hoping to turn it into the studio in the next couple of weeks. Knock on wood they love it and the movie gets a fresh breath of life very soon.

Which scene were (or are) you most excited to tackle?

Well, I just worked on the weekend, from the first book, the Jace-and-Clary-in-the-greenhouse scene.

Definitely a fan favorite...

Oh, god. It's very romantic and really fun. So that's been a lot of fun. And just sort of helping bring those characters to life on the screen has really been a joy. It's a fantastic world.

Have you had any discussions with Cassie?

I have. I've spoken with her and we've emailed each other. I've had a couple questions for her. She's been very collaborative and wonderful and extending herself to me because there is so much mythology involved. Occasionally, I'll just call her and say, 'Tell me again. What's that rule?' She's been fantastic, and she's been extremely collaborative and excited about this movie, as so many people are.

Are you familiar with the work of stars Lily Collins and Jamie Campbell Bower?

I know of them. I know of their work. I think it's fantastic casting. I think they're going to be terrific. I love how these characters sort of grow and transform throughout the book series. So it's going to be very fun for actors to play these parts.

Check back in with Hollywood Crush tomorrow as Marlene dishes about the "PLL" Halloween episode!

Are you excited that Marlene is almost finished with the "Mortal Instruments" script?