<P> The following day, the group finds that the hotel staff and the manager have been murdered, and the two - way radio, their only way of contact, has been destroyed . Isolated, Julie tells the others about the previous summer . Tyrell suspects that Estes, the boat hand porter, is the killer, since he is the only one who cannot be found . The group goes to Estes' apartment, searching for clues . They find Julie's toothbrush and Karla's hair tie, concluding Estes has been using voodoo to protect them . Estes appears and leads them to a graveyard in the forest with the graves of Ben's wife and daughter, and an empty grave and tombstone with Julie's name . Estes explains that Ben and his wife Sarah had two children: son Will and daughter Susie . Ben murdered Sarah in the hotel room that Julie is staying in when he found out about her affair and her plans to leave him with their children . </P> <P> Estes goes missing, and Will volunteers to find him . Julie, Karla, and Tyrell return to the hotel and gather supplies to defend themselves . They head to the hotel kitchen for something to eat, and find Nancy, the bartender, hiding in the freezer . Will finds Estes, but he attacks Will while Ray takes a boat to the island . Ben appears and stabs Tyrell in the throat with his hook, killing him . The girls retreat to the attic, where Karla is attacked by Ben . They both fall through to the hotel bedroom below . Karla runs from the room and jumps onto the greenhouse . Julie and Nancy rescue Karla and run to the storm cellar to take refuge . They find that the storm cellar stores Ben's victims . Will bursts in and convinces the girls to head back to the hotel, stating that he saw Ben on the beach . </P> <P> Back at the hotel, Julie sees Will is bleeding from his stomach, so Nancy takes Karla to find a first aid kit . Nancy and Karla find Estes has been impaled with a harpoon . Ben appears and kills Nancy . Back in the lobby, Julie is tending to Will, unable to find a wound . Will admits this is because it is not his blood . He asks Julie what her favorite radio station is, revealing he was the radio host and killed Estes . Will drags Julie to the graveyard, and tells her he is Ben's son . Ben appears and attacks Julie . Ray arrives, and a fight ensues between him and Will . When Ben tries to stab Ray, he accidentally kills Will instead . While Ben is distraught from killing his son, Julie takes a gun and shoots him in the chest . Ben falls dead into the grave made for Julie . Back at the hotel, Karla is found alive . The three are rescued by the coast guard . </P> <P> Sometime later, Ray and Julie have married and are in their new home . Ray is brushing his teeth before bed and Julie is in their bedroom . The bathroom door is quietly shut and locked while Ray is occupied . Julie sits down on her bed, looks in the mirror, and sees Ben under the bed . She screams as Ben grabs her feet with his hook and hand and pulls her under leaving her fate unknown . </P>

Who is the killer in i still know what you did last summer