Katya and Gleb are happiy married couple with a small son. Nothing threatens their love and family until the young woman leaves for holidays with their kid and a friend to the seaside. Gleb, busy with urgent work, has to stay home. At the resort, Katya meets handsome Alexander and becomes besotted with him so much that falls into his arms without thinking. However the vacation finally ends and the lovers say goodbye. Here, it would seem, the banal resort romance is over, but from the moment of separation the real detective story begins - Alexander starts stalking Katya insisting on meetings. He also sends Gleb messages compromising his wife, and then, having not achieved the desired result, kidnaps their son. By a strange coincidence Gleb's company faces serious problems - Who is this mysterious Alexander? And what does he really want?