Set in a fictional near-future, it simulates how the UK government might respond to a Russian attack on British soil. Real former politicians, military leaders, and intelligence officials - including Michael Gove, Nicola Sturgeon, and Penny Mordaunt - play key government roles in a COBR-style crisis room. Blending documentary and drama, the series aims to give viewers an inside look at high-level decision-making during a national security emergency.