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  • Published: 22 March 2022
  • ISBN: 9780593102688
  • Imprint: Berkley
  • Format: Paperback
  • Pages: 352
  • RRP: $38.00

What the Devil Knows




Magistrates are being murdered and a case once thought to be closed might be wide-open in this gripping historical mystery from the USA Today bestselling author of Who Speaks for the Damned.

Sebastian St. Cyr thought a notorious killer had been brought to justice until a shocking series of gruesome new murders stuns the city in this thrilling historical mystery from the USA Today bestselling author of Who Speaks for the Damned.

It's October 1814. The war with France is finally over and Europe's diplomats are convening in Vienna for a conference that will put their world back together. With peace finally at hand, London suddenly finds itself in the grip of a series of heinous murders eerily similar to the Ratcliffe Highway murders of three years before. 

In 1811, two entire families were viciously murdered in their homes. A suspect--a young seaman named John Williams--was arrested. But before he could be brought to trial, Williams hanged himself in his cell. The murders ceased, and London slowly began to breathe easier. But when the lead investigator, Sir Edwin Pym, is killed in the same brutal way three years later and others possibly connected to the original case meet violent ends, the city is paralyzed with terror once more. 

Was the wrong man arrested for the murders? Bow Street magistrate Sir Henry Lovejoy turns to his friend Sebastian St. Cyr, Viscount Devlin, for assistance. Pym's colleagues are convinced his manner of death is a coincidence, but Sebastian has his doubts. The more he looks into the three-year-old murders, the more certain he becomes that the hapless John Williams was not the real killer. Which begs the question--who was and why are they dead set on killing again?

  • Published: 22 March 2022
  • ISBN: 9780593102688
  • Imprint: Berkley
  • Format: Paperback
  • Pages: 352
  • RRP: $38.00

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Praise for What the Devil Knows

Praise for C. S. Harris and the Sebastian St. Cyr Mysteries

“St. Cyr is a brawler and his tough sleuthing is admirable....This series is a favorite.”—The New York Times Book Review

“Sebastian St. Cyr is everything you could want in a Regency-era nobleman-turned–death investigator: uncannily clever, unwaveringly reserved, and irresistibly sexy. The entire series is simply elegant.”—#1 New York Times bestselling author Lisa Gardner

“Harris is a master of the genre.”—The Historical Novels Review

“The mystery highlights the circumscribed course of women’s lives of the Regency era while exposing the rot that underlies the period’s glitter...highly recommended for lovers of historical thrillers.”—Library Journal (starred review)