The provided episode meticulously details Operation Cerberus, a German naval maneuver during World War II in which a squadron of heavy warships, including the battleships Scharnhorst and Gneisenau, moved from Brest to German ports via the English Channel. The episode comprehensively covers the background to the operation, focusing on the British air offensive against the ships in Brest and the role of Ultra intelligence. It systematically outlines the prelude of the operation, including both the German plan (Unternehmen Cerberus and Unternehmen Donnerkeil for air cover) and the British contingency plan (Operation Fuller). The majority of the episode is dedicated to a chronological account of the battle itself, describing the failure of British forces—the Royal Navy, Fleet Air Arm, and RAF—to intercept the German ships, largely due to successful German deception, jamming, and poor British coordination. Finally, the episode analyzes the aftermath, concluding that while the operation was a tactical German victory, it was a strategic failure, a sentiment echoed by the critical British inquiry that followed the "débâcle."