ABSTRACT Light Prop for an Electric Stage was presented in 1930 as a prototype for a new kind of mechanical theater that was meant to spark future partnerships between art and industry. Although it was never put into industrial production, Light Prop circulated as an early example of kinetic sculpture, as documented in a highly composed film, in photographs and in textual accounts. In 2016, the Harvard Art Museums and metaLAB (at) Harvard filmed Light Prop and its 2006 replica under highly controlled conditions. The resulting comparative media reveals how László Moholy-Nagy’s film served as the “design fiction” guiding the replication and conservation of Light Prop.