Strange tide
(Book)

The River Thames is London's most important yet neglected artery. When a young woman is found chained to a post in the tide, no-one can understand how she came to be drowned there. At the Peculiar Crimes Unit, Arthur Bryant and John May find themselves dealing with an impossible crime committed in a very public place. Soon they discover that the river is giving up other victims, but as the investigation extends from the coast of Libya to the nightclubs of North London, it proves as murkily sinister as the Thames itself.