It is 1805, and England is in the midst of her war with France under Napoleon. Matthew Pryde, employed as engineer at a coal mine in Kent, is regarded as the perfect "spy" to send across the English Channel to investigate rumours that the French are digging a tunnel underneath the Channel. Matthew travels to France, accompanied by the mysterious Mr Black - and the rather unexpected addition of the unconventional Kate Denton - to try to find the existence of a tunnel on the French side.
Returning to the Dundee of 1860 after years in the army, Robert Douglas finds employment with George Gilbride, a whaling-ship owner known as the Wizard. Drugged by sinister gangster John Wylie, Douglas wakens on board the steam-whaler Redgauntlet bound for the Artic, and discovers that his companions believe the ship is haunted and do not expect to return. After an initial clash, Douglas befriends the ship's mate, "Bully Houston", and together thay begin to unravel a year-old mystery.
Northumberland, 1804: Matthew Pryde, a young engineer, is sent to the small coastal village of Onswick to survey an offshore island, known locally as the Black Corbie. He must persuade the local landowner that a lighthouse needs to be built to prevent the high number of fatal shipwrecks that occur there. However, after suffering violence and intimidation, Matthew realises that the locals are deeply against the project.