The Cask, by Freeman Wills Crofts (epub/Kindle/pdf)

When a strange container is found in a busy London shipping yard, its contents point to murder. The cask is from a consignment of French wine, but it is bigger than the rest, its sides reinforced to hold the extraordinary weight within. Unfortunately, the longshoremen bringing it onto the London docksaccidentally break it open, spilling out a treasure of gold sovereigns.

As workers cram the spilled gold into their pockets, an official digs through the opened cask, which is supposed to contain a statue. Beneath the gold he finds a woman’s hand—as cold as marble, but made of flesh. He reports the body to his superiors, but when he returns, the cask has vanished.

The case is assigned to Inspector Burnley, a methodical Scotland Yard detective, who will confront a baffling array of clues and red herrings, alibis and outright lies, as he attempts to identify the woman in the cask—and catch the killer.