Nell, Simon, and their boy Art are ready to welcome friends and family for what promises to be a perfect Christmas gathering. Perfect except for one thing: everyone is going to die.

At the beginning of Paris fashion week, a beautiful young model is brutally murdered. Investigative journalist Madison Castelli, certain that it is more than the “crime of passion” the French press says, comes to Paris to follow her story.

Two strangers are drawn to a mysterious pharmaceutical trial that will, they’re assured, with no complications or side-effects whatsoever, solve all of their problems, permanently. Things do not go as planned.