(This is only a brief summary of the tale.)

A king decides to go on a journey and they sail to an island where they are attacked by wild beasts. Victorious, they travel inland and come to a beautiful garden where the lake warns them of a 7-headed serpent. The lake tells them they will be punished, but not killed if they lay their clothes on the ground for the dragon to walk on. This they do and their punishment is to sacrifice 12 youths and 12 maidens every year. They do this for many years.

Years later an old woman goes to the childless Queen and sells her an apple that brings children and the Queen eats it, throwing the core outside for a horse to eat. In time the Queen and the horse both had boys that drew up together.

Eventually the horse takes the boy to a convent and the boy, now 19, talked to an old Abbess who tells him how to kill the serpent.

The boy sneaked cotton into the serpents bedchamber, stuffed the warning bells with the cotton and took down the one sword that could kill it. After slicing its tail to wake it, he sliced off each head in turn, thus saving his people.