Sky City is a proposal for a self-contained vertical metropolis in Tokyo, designed to hold more than 100,000 residents inside a single structure and, on completion, to stand as the tallest building in the world. The film walks through the engineering behind that ambition: sections of the tower reserved for homes, offices, schools, and hospitals, all linked by high-speed elevators and escalators, with parks, gardens, and sports facilities built into the lower levels instead of left outside the building entirely. It spends real time on the sustainability systems, solar panels, wind turbines, and rainwater harvesting, plus a rooftop greenhouse where residents could grow their own food. Given Japan's exposure to earthquakes and typhoons, the film also covers how architects have built disaster resilience into the foundation itself. Beyond the hardware, it raises the harder question of what daily life looks like when work, school, and leisure never require leaving the building, and what that kind of enclosure does to a community.