When the body of a woman believed to have jumped into the Thames is discovered on Edgware Road and her head is pulled from the dark muddy waters of the river 10 miles away, William Pinkerton vows to solve her mysterious death in an attempt to find a thief who always escaped his father, the founder of famed Pinkerton Detective Agency. This starts a sweeping historical epic that travels from London in 1885 to diamond mines in South Africa and America during its Civil War, before returning to London for a gripping finale.