Kevin Durand and Robert Maillet are set to join the cast of Screen Gems and Constantin Films “The Mortal Instruments.”

Lily Collins and Jamie Campbell Bower also star in the pic helmed by Harald Zwart.

Based on Cassandra Clare’s bestselling young adult book series, the story follows Clary Fray, a seemingly ordinary teenager who discovers she is the descendent of a demon-hunting clan. Durand and Maillet will play Pangborn and Blackwell, an antagonist duo in the pic.

Robert Kulzer and Don Carmody will produce and Bob Shaye, Michael Lynne, Martin Moszkowicz will exec produce.

Durand is currently filming “Devil’s Knot” and can be seen next David Cronenberg’s “Cosmopolis.” He is repped by WME, Alchemy Entertainment and attorney Dave Feldman.

The Character’s Agency repped Maillet’s can be seen next in Legendary’s “Pacific Rim.”