Five friends have decided to set out on a vacation to the beautiful island of Formentera, where they expect to spend their days full of fun and debauchery. On one of their outings they come across a cave set in a cliff and decided that it would be exciting to investigate it and see what they could find. However it isn't long before the group realizes that they have lost their way, prompting them to try to find the exit instead of exploring further. Unfortunately they are unsuccessful in their attempt and are forced to stay the night and as a result they find their sanity weakening. As the lack of food, water, and sunlight paired with the isolation from society due to a lack of cell phone reception begins to take its toll on the group, they find themselves beginning to panic and hallucinate. Eventually their survival will rely on them making certain decisions that will change them forever.