In the garden of a large Georgian villa in Southwest London, socialites and politicos swap gossip and sip Pimm's while making snide remarks at each other. Not far from this frivolity, though, a body has been discovered in the River Thames. At first, it appears to be an unfortunate accident, but the death is connected to this gathering of who's who in a way that may spell scandal.

Meanwhile, Detective Inspector Caius Beauchamp, attempting to enjoy an evening at the theatre, is shocked to discover another dead body, just a few seats away. The death is linked to the decades-old disappearance of a fourteen-year-old girl at a boarding school in Cornwall. Now Caius has two cases on his plate, but if he wants the resources to solve the tragic mystery of the girl's disappearance, he will have to take new orders from a shadowy government minister who contends that the accidental drowning in the Thames was anything but.

As Caius, along with his associates Matt Cheung and Amy Noakes, investigates these parallel cases, he plunges into the exclusive world of money, title, and power as only England can dish it up, where justice is available only to the privileged.