The Nakagin Capsule Tower, designed by Kisho Kurokawa and completed in 1972, is an exemplary work of post-war Japanese architectural movement Metabolism. Today, however, this historic building is in danger of demolition. Why do we need to preserve a building? What are the difficulties of preservation? Is demolition a tragedy or a natural phenomenon for modern architecture? Tracing the history of postwar Japanese architecture and reviewing the characteristics of the Nakagin Capsule Tower, this documentary examines the meaning of preservation and demolition from various points of view. The documentary includes interviews with residents of the Nakagin Capsule Tower, an architectural historian, a former Kurokawa office architect who was in charge of the Nakagin Capsule Tower project, Kurokawa’s son, and leading architects Arata Isozaki and Toyo Ito.