Jean Seymour was once Second Desk. She had once had the ability to control networks, communicate with spooks and hatch a plot or two. However, her violent death at the hands of a believed Russian agent sends MI5 into a frenzied panic, which calls upon the services of Somerset's Quiet Street branch of the service. However, while the new Second Desk, Sir David Ripley is frantically arranging a meeting with an oligarch to discuss security, the punishment detail led by Edwin Slaughter looks into the murder of Jean Seymour. What they uncover will shock Quiet Street and MI5 to the core.