The fantasy adaptation The Mortal Instruments: City of Bones has added Lena Headey, Jared Harris, and newcomer Godfrey Gao to its growing cast.

This adaptation of Cassandra Clare's novel series centers on Clary Fray (Lily Collins), a young woman living in New York City who learns she is a descendant of a demon-hunting clan. Lena Headey is playing Jocelyn Fray, Jared Harris portrays Hodge Starkweather, and Godfrey Gao has signed on to play Magnus Bane. Other cast members include Jamie Campbell Bower, Jemima West, Robert Sheehan, Robert Maillet, and Kevin Durand. Read on for more information about this adaptation from the studio press release.

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About the Books:

The Mortal Instruments is a series of six young adult fantasy books written by Cassandra Clare and published by Simon & Schuster/Margaret K. McElderry Books. In the series' first book, the #1 New York Times bestseller The Mortal Instruments: City of Bones, set in contemporary New York City, a seemingly ordinary teenager, Clary Fray, discovers she is the descendant of a line of Shadowhunters, a secret cadre of young half-angel warriors locked in an ancient battle to protect our world from demons. After the disappearance of her mother, Clary must join forces with a group of Shadowhunters, who introduce her to a dangerous alternate New York called Downworld, filled with demons, warlocks, vampires, werewolves and other deadly creatures.

About the Film:

The Mortal Instruments: City of Bones is a Constantin Film and Unique Features Production, directed by Harald Zwart (The Karate Kid) from a screenplay by Jessica Postigo Paquette and I. Marlene King (Pretty Little Liars). Robert Kulzer is producing for Constantin Film alongside Don Carmody. Executive Producers are Robert Shaye and Michael Lynne for Unique Features and Martin Moszkowicz for Constantin Film. Principal photography will begin August 20, 2012 in Toronto, Ontario. Screen Gems will release in the United States August 23, 2013. Mister Smith Entertainment will handle foreign distribution for Constantin Film. Sony Pictures Consumer Products has acquired the licensing rights. The film is a Canada-Germany Co-Production.