1857. Joel Heygate is the popular stationmaster at Exeter St David's railway station. So when the charred remains of a body are discovered in the embers of the town's annual Bonfire Night celebration, everyone is horrified to discover that they belong to Mr Heygate.

Inspector Robert Colbeck and his assistant Victor Leeming are dispatched to Exeter with all due haste, and quickly unearth a number of suspects. But as Colbeck closes in on the killer, he finds himself in mortal danger. Can justice prevail, or will his beloved Madeleine be robbed of a husband on the very eve of their marriage?