A killer is targeting American tourists in Edinburgh, Scotland. Three dead solo female travelers were found strangled in the closes off the Royal Mile. FBI Agents Kate Walsh and Declan James are sent to investigate at the height of the Christmas tourist season. Police Scotland is without any leads.

No one believes these crimes are the killer's first - and they aren't. Soon they discover similar murders of solo female travelers across Europe. Agent Walsh is determined to keep this killer in Edinburgh even if she has to use herself as bait.

When an international art thief known as the Phantom is identified as a suspect, Agent Walsh is hard-pressed to believe it. The two must form an unlikely alliance to find the truth. Can she trust him in time or will the killer escape to another European city to kill again?