Famed architect Jeremy Angust is approached on his trip to the Paris Airport by a chatty girl named Texel Textor who needs a ride. He obliges and after they part ways at the airport entrance, he misses his flight. As he settles in the lounge, he encounters the mysterious young Texel again, who insists on telling her strange story — and the conversation grows stranger and more twisted until it turns sinister and deadly.
After a near-death drowning accident, a young boy's family is horrified to discover he has become possessed by a legendary demon from the depths of the lake. As the family races against time to save the boy's soul, the evil monster inside the child tears the family apart as it seeks to destroy everyone in its path.
Set against the backdrop of a summer on the French riviera, the Roussier family and its fragile equilibrium is shaped by the uncertain diagnosis of 13-year-old Bertille, who suffers from a severe disability. Her parents and older sister Marion live in constant fear of losing her. Disconnected from typical teenage dreams, Marion seeks escape in a relationship with an older boy. When a new diagnosis emerges, the family’s future is redefined, opening up unexpected possibilities. Bertille will live, and so will her family.
