Messapo, King of Etruria, retired to the sea to spend his old age in peace, aboard a magical sailing ship in the company of his faithful sailor Caronzo. Despite his various adventures, Messapo does not seem to feel the weight of the centuries on his shoulders, for him the passage of time is slow, he is the son of the lord of the seas, Poseidon. Over time, however, the people of the sea have suffered many abuses due to pollution. The sirens, with the support of the god Hermes, have obtained legs to be able to enter the society of men and avenge the wrongs suffered. Messapo will hold up a double game, and a criminal siren will challenge Poseidon to become Goddess. It will be thanks to the sons of Messapo that Poseidon will be able to restore
the balance between the two worlds.