Five years after the earthquake and tsunami that triggered the unprecedented trio of meltdowns at the Fukushima Daiichi nuclear power plant, scientists and engineers are struggling to control an ongoing crisis. What’s next for Fukushima? What’s next for Japan? And what’s next for a world that seems determined to jettison one of our most important carbon-free sources of energy? Despite the catastrophe—and the ongoing risks associated with nuclear—a new generation of nuclear power seems poised to emerge the ashes of Fukushima. NOVA investigates how the realities of climate change, the inherent limitations of renewable energy sources, and the optimism and enthusiasm of a new generation of nuclear engineers is looking for ways to reinvent nuclear technology, all while the most recent disaster is still being managed. What are the lessons learned from Fukushima? And with all of nuclear’s inherent dangers, how might it be possible to build a safe nuclear future?