In this High Victorian detective novel, Dyke Darrel investigates the robbery of the Central Railroad’s midnight express, during which Dyke’s friend Arnold Nicholson, a messenger, was murdered. He is helped by his sister Nell, with whom he was supposed to go on holiday. Dyke Darrell turns "the Gotham of the North" - as he calls Chicago - upside down in search of the culprit. On the way he encounters old ennemies, kidnappers and masquerades, as he tries to solve "the most audacious crime of my remembrance."
Allan Frank Pinkerton was the son of Allan Pinkerton (1819-1884), the Scottish-American spy, detective and founder of the Pinkerton National Detective Agency, which rose to fame in the mid-19th century. Inspired by his father work and the agency’s archives, A. Frank — like many other authors at the time — created highly sensationalised and popular novels based on the Pinkerton cases.