It's Christmas, in Paris! Computer expert John Hunter plans a surprise marriage proposal to criminologist Marin Ryan, on top of the Eifel Tower. However, when a string of murders sends violent tremors through the City of Light, the couple interrupts their celebratory plans to team up with the local police on a hunt for "The Christmas Killer." The city of Paris, decorated with holiday lights and newly fallen snow, provides a sumptuous locale for the investigation.