Russia's March 2022 invasion of Ukraine reopens a question Europe thought it had settled decades ago: who should hold nuclear weapons, and how many. The film tracks the debate that followed Vladimir Putin's invasion, as NATO members weigh whether deterrence built for the Cold War still holds against a Russian leader willing to invade a neighbor outright. Officials, analysts, and military voices lay out the arguments for expanding nuclear deployments in Europe against the risks of provoking the very escalation such weapons are meant to prevent. The film traces how Putin's rhetoric and troop movements have already shifted policy conversations in capitals that spent thirty years assuming large-scale war on the continent was over. It is less interested in spectacle than in the calculations happening in ministries and alliance meetings, where the cost of miscalculation is measured in cities. The result is a sober look at a debate most of Europe hoped it would never have to reopen.