Maurice Mundy, recently retired detective constable at the Metropolitan Police, has returned to join Scotland Yard's Cold Case Review Team. Ten years ago a twelve-year-old boy was murdered, his body left floating in a nearby pond. A second look at the case soon reveals that a sex worker was also murdered nearby on the same night.

While nothing linked the two murders at the time, it is one of a number of attacks on sex workers over a twenty-year period that Essex Police are still investigating as part of Operation Moonlight.

Known as a loose cannon who doesn't always play by the rules, Mundy is in danger of ruffling more than a few feathers as he probes deeper into the events of that fateful night. Will his maverick approach lead him to the truth, or will it prove to be a dangerous step too far?