<P> The following day, Kale and Cleo are arrested for the murders . A container full of pulled teeth is found in one of their bags . The two couples are relieved by the arrests, and they continue their hike to the beach . Cliff rents two kayaks so he and Nick can explore a marine cave . </P> <P> As Gina idly looks through the photos on Cydney and Cliff's video camera, she is terrified when she realizes the couple are not who they claim to be . Gina sets off after Nick and Cliff, while Cydney chases after Gina . </P> <P> Flashbacks reveal that Cliff and Cydney are drug - addicted sociopaths who murdered the newlyweds . They kill people and steal their identities in order to, as Cliff explains, "live a hundred different lives and achieve a kind of immortality". It is also revealed that "Cliff" had planted the bag of teeth in Kale and Cleo's bag to frame them for the murders . </P> <P> In the Sea cave, Cliff suddenly reveals his true murderer identity and shoots Nick in the head . Gina witnesses this from the cliffs above . Then Cliff shoots at her, but misses . Cydney sneaks up on Gina and attacks her . Gina is stabbed in the leg but manages to push Cydney off the cliff into the water . </P>

Who was the killer in the perfect getaway