The Cask by Freeman Willis Crofts is on sale at Amazon UK for £0.99 today.
"From the Collins Crime Club archive, the seminal first novel by Freeman Wills Crofts, once dubbed ‘The King of Detective Story Writers’ and recognised as one of the ‘big four’ Golden Age crime authors.
The unloading of a consignment of French wine from the steamship Bullfinch is interrupted by a gruesome discovery in a broken cask leaking sawdust and gold sovereigns. But when the shipping clerk returns with the police, the cask and its macabre contents have gone. Following the clues to Paris, Inspector Burnley of Scotland Yard enlists the help of the genial French detective M. Lefarge to check motives and alibis in their hunt for evidence of a particularly fiendish murder.
This Detective Story Club classic is introduced by Freeman Wills Crofts himself in a unique preface from 1946 about The Cask’s origins."
https://www.amazon.co.uk/dp/B01CY4SU2E