In a future where the British monarchy is on the brink of collapse, King Charles III must navigate the treacherous waters of politics and family dynamics when he refuses to sign a controversial bill into law, sparking a constitutional crisis that threatens to upend the entire institution. Protests erupt across the country, with Prince Harry caught in the middle as his relationship with a republican girlfriend puts him at odds with his father's actions. As tensions escalate, Charles must confront the consequences of his decisions and the legacy of his mother, Princess Diana, in a climactic showdown that will determine the future of the monarchy.