The girls Cleo, Emma, Bella and Rikki went on holiday to Mako Islands where they met some local boys including Louis, Elliot, Marco and Ryan. They began surfing lessons from the boys and Emma and Marco grew closer. They were invited to a party on Zane's private yacht on Saturday night. At the party, Emma fell into the water and nearly drowned but Marco saved her. Later that night, a large carnivorous sea creature was spotted in the water near the yacht. The next day, parts of a body were found floating, and one of the girls, Rikki, was missing.