This Italian-French mystery thriller follows Daniel Boltanski, a celebrated but intensely private writer who publishes under a pseudonym to maintain his anonymity. While traveling to Italy for his stepson’s wedding, he has a passionate one-night stand with a mysterious young woman he meets on a ferry. The next morning at the wedding, he is horrified to discover that the woman, Mila, is actually the bride—his stepson Fabrizio's new wife. Despite the danger and the moral boundary, the two continue their affair, leading to a dark game of blackmail and obsession that threatens to expose Daniel’s secret identity and destroy his family.