It is the summer of 1958 in wealthy Lake Geneva, where an enigmatic young Frenchman begins an affair with a beautiful starlet under the watchful eye of her flamboyant elderly mentor. But in a season full of secrets, is truth the most elusive passion of all?

A police detective catches wind of a brutal serial killer - the same serial killer who is responsible for the deaths of her parents, 30 years earlier.

What happened, that 24th of December? This is what officer Chartier wants to find out. To understand, he will have to go back 48 hours earlier to Franck's Christmas eve. Franck is an insignificant drama-teacher by day, but also belongs to a nameless and leaderless militant organisation - the Animal Liberation Front. These characters are bound by a limitless empathy towards mistreated animals, and will have to show courage to complete a mission they have been preparing for months.