A pair of entrepreneurs with more bravery than brains hit upon the idea of blood surfing: spreading chum in the water in order to attract sharks, then hopping on a surfboard and riding through the middle of the pack. As they're filming their promotional documentary, the fun gets interrupted by a thirty-foot long salt water crocodile that begins snacking on everyone in the expedition. Will any of them make it back to civilization?

Francesca is a pediatrician who is dedicated to both motherhood and children, married to another physician, Pedro. Following the birth of a new child, Francesca begins to suffer from postpartum depression. Following the advice of friend and psychiatrist Jean, the couple move to a new home away from the city. But Francesca's obsession with her new baby engulfs her. Regardless of Pedro's and Jean's attempts to help her, she seems to drift dangerously close to madness. And to make matters worse, she is starting to hear and see things. Furtive figures and ghostly shadows start tormenting her. The large house in which she and her family live alone seems to hide terrible secrets. Both the cellar and the attic are locked and barred to the family, and it is from both these places that Francesca receives nocturnal visits that are slowly driving her mad.