The film's plot unfolds in a magical world where a young king's son, Culhwch, sets out in search of the stolen fairy Olwen. The girl has been kidnapped by a sinister giant in black robes, and Culhwch must overcome numerous obstacles to rescue her. His journey is incredibly dangerous, as he encounters magical creatures and enchanted objects along the way. Gradually, the hero realises that not only physical strength but also kindness of heart, forgiveness, and intelligence can help overcome difficulties.