Kevin Zegers has joined the cast of The Mortal Instruments: City of Bones for Constantin Film and director Harald Zwart. We reported last week that Lena Headey and Jared Harris joined the cast.

The story centers on Clary Fray (Lily Collins), a young woman living in New York City who discovers she comes from a long line of demon hunters. The actor will portray Alec Lightwood, the homosexual brother of Jemima West's Isabelle. He despises Clary since he is in love with Jace (Jamie Campbell Bower), who has feelings for the protagonist. Kevin Durand, Robert Maillet, and Robert Sheehan also star.

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Jessica Postigo Paquette and I. Marlene King wrote the screenplay, adapted from Cassandra Clare's novel. Production is slated to begin August 20 in Toronto.