Multidisciplinary design firm, Castor is known for recontextualizing discarded materials. Three of their most iconic designs are lights repurposed from items most people intend for the trash - the Tube Light from used fluorescent tube lamps; the Tank Light from expired fire extinguishers; the Invisible Chandelier from piles of assorted burnt out light bulbs - all of which are the subject of this film, CASTOR IS FRENCH FOR BEAVER.