A Parisian couple decides to sell an unsanitary basement in their building. A very ordinary, nondescript man, Mr. Fonzic, shows up to buy it. Nothing unusual there, until the man moves into the cellar and makes it his permanent residence. The couple tries desperately to cancel the sale but to no avail. Worse, Mr. Fonzic becomes a threat to their family as he befriends their teenage daughter on whom he seems to exert a perverted influence.
The Man in the Basement is a 2021 French thriller drama film written by Marc Weitzmann, Philippe Le Guay and Gilles Taurand, directed by LeGuay and starring François Cluzet, Jérémie Renier and Bérénice Bejo.