Orpheus' Song (Orfeos Traum) 4 years old

Two best friends from Berlin win a trip to Greece. On their excursion, they get lost on an island. They wander in the woods until they find an abandoned village where they encounter a mysterious creature, who calls himself Hercules. They spend the night together in a cave and dream a mystical dream. On the next day, nothing between the two will be like it was before.