When Julien and his wife move to Amsterdam to help look after their grandchild, the Chief of Police, who happens to be Julien's old girlfriend, seeks out his help in finding a young sex worker who has gone missing. As Baptise rapidly becomes embroiled in a case that peels back layers and layers of atrocity in the sex trade and drugs, nothing is as it first seems. For Julien Baptiste the beautiful streets, canals and houses of Amsterdam hide dark, deadly secrets.