Collateral Rooms is an interactive live-art installation developed for the Frankfurter Buchmesse 2016 - the most renowned book/creative design fair in the world. For this installation CREW adopted the floor plan of theBarcelona Pavilion of Mies van der Rohe, made in 1929. The futuristic set-up will consist of simple walls, channeling a 3D real time architectural space that plays with virtual transparency, mirrors, axis, sight lines and real time composited material textures. The illusory indoor and outdoor views will contains sea views, indoor columns, material of glass, steel etc, all adapted to the perspective of the viewer. All these images will be computer graphics, internet images and filmed images, all displayed by a live compositing system. Collateral Rooms incorporates all the expertise that has been developed in'viewer dependent images'. When the spectator enters the space, the'motion capture system'will regularly choose for one person - fragmenting the virtual environment for others. No part will be real except for the wall planes. The'motion capture system' and the viewer's free movement can supply infinite viewpoints and extensive visual effects.