The story follows Luca, a sea monster who lives under the sea near the Italian city of Portorosso. One day, he discovers a mysterious object from the surface and meets Alberto, a fellow sea monster who is not afraid to venture to the surface. They become friends and start exploring the world above the water. They meet a human girl named Giulia and her father, who befriend them and help them participate in a competition called the "Portorosso Cup" where the winner gets a Vespa.
Luca, Alberto, and Giulia form a team and face various challenges, including a rival named Ercole Visconti who tries to sabotage them. Despite the obstacles, they manage to win the competition, and their victory is met with acceptance and celebration from the townspeople.
The story concludes with Luca, Alberto, and Giulia parting ways as Giulia returns to school, but they promise to stay in touch. The credits scene shows the friends keeping in touch and continuing their lives, with Luca and Alberto visiting each other and having more adventures together.
1. Luca is a sea monster who lives on the coast of an Italian city.
2. Luca's life changes when he discovers a mysterious object, a clock, from the surface.
3. Luca meets Alberto, a boy of the same species, who teaches him to walk on land.
4. Alberto lives with his father but is often left alone.
5. Luca and Alberto befriend a girl named Giulia, who helps them prepare for a competition.
6. The competition consists of swimming, eating, and cycling.
7. Luca and Alberto's goal is to win a Vespa motorcycle.
8. The group faces challenges, including a rival named Ercole Visconti.
9. Luca and Alberto's friendship is put to the test when Alberto's father abandons him.
10. Luca decides to participate in the competition alone, but Alberto eventually joins him.
11. The competition ends with Luca and his friends being accepted by the townspeople as sea monsters.
12. Luca's parents and grandmother are invited to Giulia's father's house for dinner.
13. Giulia has to return to school, and Alberto gives her a ticket to visit him.
14. Luca and Alberto promise to stay in touch and remain friends.
15. The story concludes with the friends keeping in touch and living happy lives.