Who was the mysterious Hector Lightfoot? What was he up to when he disappeared, and who were the two ghosts once seen in his house? School friends Jamie and Todd are destined to find out when they go to London to spend a weekend with Jamie's Uncle Simon, who now lives in that very house. Soon after they arrive, Jamie has a frightening encounter with the two ghosts. Hector, a veteran from the First Afghan War, joined a covert expedition to China, and afterwards worked on a secret Government project in an underground lab at the British Museum. He vanished suddenly, and was never heard from again. Simon takes the boys to the lab, where they find a strange contraption - which, unknown to any of them, is a time-travel device. When the building is struck by lightning, the device is energised, and sends the boys back in time to the year 1862. There, surrounded by danger and exposed to disease, they are sucked into a life of crime in order to survive. Only if they can find Hector will they have any chance of getting home again. But why has he gone into hiding? Who is the man after him and what does he want? As the boys struggle to escape back to their own time, Jamie becomes convinced that the two ghosts he saw earlier are following them...