After a crossbow bolt kills a birdwatcher in a remote site on the
Thames, the Metropolitan Police discover they have another serial killer
on their hands. The killer leaves no trace, and Detective Inspectors
Shepherd and Vance are faced with a puzzle that threatens to erupt into
an international scandal.
Soon after, a virtuoso pianist loses his life in the same manner. The
murders are all connected to the river Thames, but the waters are
muddied by the involvement of British and Russian secret services.
After a man is arrested for the murder, Shepherd is certain that he is
the culprit. But what do the international organizations have to do with
the case, and who is the killer?