Hélène meets Thomas, a charming 30 year-old full of energy and attention who quickly appears to be a providential man by taking care of Hélène’s problems, one by one. As a lover of old stones, a history of France buff, he even figures out a solution to the delicate matter of renovating the castle. When the rest of the family meets him, everyone succumb to his charm and Hélène appears more and more as the saviour of the clan. Yet, by coming to the rescue of this family, this “providential man” has just put down the first milestone of a devilish scam. He’s a brilliant conman who instantly knows what people want to hear, and he’ll work hard on uniting the family around the idea that someone is coming after them, before he can isolate them from the rest of the world and control their actions.
Month after month, thanks to clever deceptions and devilish interpretations of random events, Thomas convinces every member of the family that their lives are in danger and that they must obey his every command to survive. Plunged into total paranoia, each three generations of the family with live under the tyranny of this man whose only goal is to strip them to their last dime. The few that resist, like Gérard, Hélène’s husband, are cast away from the clan.