With his last breath Uu's friend entrusts him with the secret of how to go to the past. Uu is an engineer and doesn't believe in miracles, but the trick works. In the past there is a pleasant, eternal summer, long hair, girls and Jenkki chewing gum. In his real life, it is autumn, his friends are bitter, the girls are married and his father is seriously ill. At the end of the day, however, Uu has to decide in which time to live his life - in the summer of the past or in the autumn of the present.