** A WATERSTONES THRILLER OF THE MONTH ** ** SHORTLISTED FOR THE CWA HISTORICAL DAGGER AWARD ** ** AN INSTANT TIMES BESTSELLER ** ** A FINANCIAL TIMES BOOK OF THE YEAR ** 'A TRULY GRIPPING READ' - GUARDIAN 'FABULOUS, A DELIGHT' - S.G. MACLEAN 'A FINE ADVENTURE REMINISCENT OF PATRICK O'BRIAN' - SUNDAY TIMES This is the secret report of Laurence Jago. Ex-clerk. Unwilling spy. Reluctant sailor. Accidental detective. New Year 1795, and Laurence Jago is aboard the Tankerville mail ship, en route to Philadelphia. Ostensibly travelling as assistant to the irrepressible journalist William Philpott, Laurence's real mission is to aid the civil servant carrying a vital treaty to Congress. A treaty that will prevent the Americans from joining with the French in the war against Britain. However, when the civil servant meets an unfortunate - and supposedly accidental - end and the treaty disappears, Laurence realises only he can now prevent war with the US. Trapped on the ship with travellers including two penniless French aristocrats, an Irish actress and a dancing bear, Laurence must hunt down both the lost treaty and the murderer, before he has a tragic 'accident' himself... The new page-turning historical mystery from the author of BLACK DROP, a 2021 TIMES Book of the Year. Perfect for readers of Andrew Taylor, Laura Shepherd-Robinson and S.J. Parris.

Prizes

Short-listed for CWA Historical Dagger 2023 (UK),Long-listed for Theakstons Old Peculier Crime Novel of the Year 2023 (UK)

A perfect storm of historical intrigue, bloody mystery and heart-stopping tension! An eighteenth century whodunnit on a ship, with a bear, a dog and a set of tarot cards. What absolutely top-sail rollicking entertainment -- Janice Hallett, author of THE APPEAL
A satisfying nautical mystery * The Times *
Intrigue, tension, memorable characters and shipboard life depicted in all its reeking authenticity add up to a truly gripping read * Guardian *
A fine adventure reminiscent of the Patrick O'Brian novels * Sunday Times *
Fabulous... A delight. Nattrass again and again had me wondering at her skill and marvellous turn of phrase in filtering complex eighteenth-century history in a way that resonates with our own times -- S. G. MacLean, author of THE SEEKER
Luscious prose, an immersive setting, and a fine eye for detail. A nautical mystery with serious historical heft -- Vaseem Khan, author of MIDNIGHT AT MALABAR HOUSE
I admired Black Drop. I loved Blue Water. Even more welcome than an extra rum ration on Christmas Day, and slips down just as easily -- Robert Lloyd, author of THE BLOODLESS BOY
Danger and mystery trapped inside a rocking barrel, far from home. Artful and authentic historical fiction at its best -- A.J. West, author of THE SPIRIT ENGINEER
I absolutely loved this book. Full of intrigue and excitement with a brilliantly-realised cast of characters and a totally immersive setting, it's a superb historical thriller -- Philippa East, author of LITTLE WHITE LIES
Ingenious and deftly plotted with a pleasing cast of characters. Nattrass's nautical detail is most effective, never overplayed and just as satisfying as any of the C.S. Foresters I adored in my olden days. A hugely enjoyable read -- Alix Nathan, author of THE WARLOW EXPERIMENT
A compelling locked room murder-mystery filled with an exquisitely drawn cast of eccentric characters. A wonderful historical naval adventure which keeps the reader guessing right to the final pages -- Louise Fein, author of PEOPLE LIKE US
I loved this rip-roaring tale of murder and intrigue on the high seas. A locked-ship mystery, and a cracking sequel to the brilliant Black Drop -- Trevor Wood, author of THE MAN IN THE STREET
Beautifully written, immaculately plotted and filled with more red herrings than the Atlantic, it takes readers on a thrilling voyage of murder and mystery. If Patrick O'Brian & Agatha Christie had ever got it together... -- Kate Griffin, author of FYNESHADE
Leonora Nattrass has woven an incredible novel against an incredible backdrop. It's a real art to combine history and intrigue and yet she has delivered it - again - with such skill -- Liv Matthews, author of THE PRANK
Brilliantly written, spine-chillingly evocative and hugely compelling. A stunning book -- Miranda Dickinson, author of THE START OF SOMETHING
A compelling and spectacular nautical murder mystery. Superbly written characters in a convincing historic setting - I loved it! -- Guy Morpuss, author of FIVE MINDS
Such a thrilling read. Characters who utterly drew me in and didn't let go until the final page. Spectacular -- J.M. Hewitt, author of THE EIGHT YEAR LIE
A brilliant thriller set on the high seas with murder, duplicity and the search for a vital treaty trying to reach Philadelphia -- James Mylet, author of THE HOMES

Leonora Nattrass studied eighteenth-century literature and politics, and spent ten years lecturing in English and publishing works on William Cobbett. She lives in Cornwall, in a seventeenth-century house with seventeenth-century draughts, and spins the fleeces of her Ryeland sheep into yarn. Her first novel, Black Drop, was published in 2021. Find her on Twitter @LeonoraNattrass