In the South Pacific Lagoon of Bora Bora there is a boy named Mako, his dog Afa, his mom, and grandfather. Every morning Mako and Afa go swimming. Mako loves to go to the island. There is a ghost shark that lives in the lagoon named Tupa that everyone is afraid of.
Mako found out that Tupa killed his father so now Mako wants to kill Tupa for revenge.
That night going to bed Mako had visions of getting revenge on Tupa for killing his father. Then the next day Makos mom asked him to go collect fruit from the island for his family, he spends so much time there that it gets dark. He collects all of his fruit and calls Afa over and they start to go back home.
Mako and Afa were on there way home when Mako sees Tupa, Mako tries to grab Afa but the boat tips a little and Afa falls into the lagoon. Mako has to decide if he wants to risk his life to save his best friend or hope Afa doesn't get hurt.
Mako grabs his spear and throws it at Tuaps eye and shoulder. Makos last throw to Tupas shoulder kills Tupa and Mako ties Tupa up and brings him to shore.
Mako has now killed Tupa and everyone now feel safe to go in the water whenever they want. The people of the island cheer in relief and Mako receives the reward from the king