Credit: Video Still

As you may remember, Pretty Little Liars creator and showrunner Marlene King was involved in another impressive project last year: she worked on the screenplay for the movie adaptation of the first book in the popular young adult supernatural series Mortal Instruments.

Now, the movie is well on its way to being finished; it hits theaters on August 23, 2013. The first full trailer has been released, and it looks as epic as anyone could ask for.

Are you excited? Check out the trailer below!

Credit: YouTube Photo: Watch the Mortal Instruments: City of Bones Trailer (VIDEO)

Catch the return of PLL Season 3 on Tuesday, January 8, 2013 at 8 p.m. ET/PT on ABC Family.

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