When the Home Secretary receives a cryptic telegram threatening to cripple Britain within days, he turns to Sidney Orebar and his top agents, Moira Hunter and Liza Hart.

As sabotage spreads across telegraph lines and railways, they uncover a hidden conspiracy led by the powerful Lord Severin Wren, aiming to plunge the nation into chaos.

Racing against time, the agents must outfight, outthink, and outmaneuver a carefully orchestrated plan—before the empire falls silent.