One day Anna Gromova, a journalist working on the "24 Hours" newspaper, saves the life of the grandson of a mysterious clockmaker. As a reward and a sign of his gratitude, the young man gives her an antique clock that possesses an extraordinary property - it can to take its owner back in time, to a recent past, thus providing an opportunity to change the course of events before they happen. However, the heroine cannot control the movements of time. But when people's lives are in danger, the clock takes Anna farther back, to a time which allows her to avert a looming disaster.