Britain’s survival depends upon keeping the sea open. Its enemies intend to close it. In the autumn of 2123, Chinese fleets advance into the North Atlantic and the English Channel, threatening the shipping routes that sustain Britain and the naval ports from which she must defend herself. Convoys become targets. Surveillance vessels conceal their purpose among civilian traffic. Submarines stalk the approaches, while political demands arrive backed by aircraft, missiles and the growing certainty that the next encounter will bring war. Against them stands a Royal Navy stretched between too many commitments. From Portsmouth and Plymouth to the Clyde and Rosyth, commanders must protect their bases, escort merchant ships and preserve enough strength to fight another day. American support brings formidable ships and aircraft, but also conflicting orders from a government whose attention is divided. Every promise of assistance must survive the distance between a conference room and a flight deck. Then an impossible fleet appears above the Earth. Robbie Burns never expected to command anything resembling the Imperial Fleet. Drawn from an ordinary life into the surviving machinery of a forgotten civilisation, he finds himself aboard ISS Invincible, surrounded by artificial intelligences whose knowledge exceeds his understanding and whose obedience requires more scrutiny than reassurance. Their ships possess extraordinary speed, protection and destructive power. They also carry the damage, uncertainties and obligations of a history he has scarcely begun to comprehend. Returning home has cost him more than he imagined. The Britain he knew belongs to the past. The country beneath him is unfamiliar, threatened and still recognisably his own . To defend it, Robbie must build a human command around machines accustomed to operating without one. Engineers demand proof behind flawless displays. Pilots must learn aircraft that can kill them long before the enemy does. Medical officers insist that wounded men remain patients regardless of their uniform. Recruits ask the practical questions that grand causes seldom answer: who pays them, who protects their families, and who has the authority to order them into battle? Imperial power offers no simple solution. A kinetic projectile fired carelessly near a populated planet could turn a military victory into a catastrophe. Every interception demands a safe line of fire; every rescue competes with another urgent task. Below, Atlantic gales scatter formations, heavy seas strain damaged hulls, and Channel rain reduces the distance between uncertainty and disaster. As the fighting spreads, British captains confront dwindling ammunition, exhausted crews and ships that must remain on station despite their wounds. Chinese officers discover that superior numbers cannot remove the consequences of rigid orders. Robbie must decide how far intervention can go before protection becomes domination, and whether the fleet’s machines will accept the limits he places upon them.
