The ambulance doctor František moves away from his wife Bohuna to his new love Helena. She has been married for several years to the successful writer Karl. However, thanks to her husband's philandering, she was by no means happy in it. It seems that František and Helena are finally waiting for peaceful days and now, on the threshold of fifty, they will finally be able to experience their satisfied love. However, their enthusiasm is not shared by their past partners.

After her mother's death, twelve-year-old Johana lives only with her father, who is clearly unable to raise her on his own. Therefore, she is sent to spend her holidays with her uncle, who lives alone on a rural farm. Johana, who is attracted to everything mysterious, discovers a mysterious German man living in an old tower in the neighborhood. Together, they search for the secret of a medieval legend about a gateway to other worlds. During their search, not only is their shared "Dänikenian" belief confirmed, but they also learn more about each other.