While equipping her husband on a business trip, Anna finds a note from her mistress and some keys in the pocket of his corporate jacket. She is amazed – because everything in their life with Oleg was so cloudless! Anna decides to follow where her husband is going and sees him at the airport with a young woman and a child. She goes home in despair, but on the way she meets an old acquaintance: 17 years ago she declared her love for him, but the guy disappeared from town and from her life. Andrew, captivated by memories, tries to restore relations with Anna. Meanwhile, her husband Oleg, who at the airport just helped a stranger, but in Moscow really went to his mistress, decides to break up with her and return to the family. Anna goes on a date with Andrew. But ... he runs away from the meeting place again, and Anna doesn't get there at all. Soon, the union of Anna and Oleg, which has already begun to collapse, is restored. But what kind of note and keys were found in the jacket? The answer will be ridiculously simple!