On the verge of concluding the trial of his life, Pierre Maillard, a cold and rigid lawyer, is forced to spend a day with the most unpredictable man imaginable. A day of madness, which seems absolutely endless to him, and where anything can happen, even the most improbable things. So why does Pierre's secretary always trip over the carpet? And why does his boss always ask him the same thing? Finally, how is it that Pierre always receives the same phone call?

It's their daughter's wedding day, and Francis and Rosalie should be the happiest parents in the world. However, the mood is not festive. Rosalie reproaches her husband for dancing all evening with a woman whom no one knows. Caught red-handed, Francis is forced to admit that this woman is none other than his mistress. Rosalie is not going to take this lying down! Time for retaliation.

Paul, a businessman, is about to radically change his life... He has planned everything down to the smallest detail: the lucrative sale of his website to a Russian company, his divorce from his wife Valérie, and his departure for a paradise island with his mistress. The only person privy to his scheme and plans is his friend Michel, a computer genius who is naive and prone to blunders, but who follows Paul like a beacon... But on the eve of this fateful day, everything changes: a short circuit causes the oven to explode just as Paul is in the kitchen. He emerges unscathed, but against all odds, he has completely lost his memory. With the help of a doctor specializing in amnesia, Michel will do everything he can to help his friend, because time is of the essence: Ilona, the emissary from the Russian company, is expected to arrive any moment to finalize the contract.