Everyone loves a good murder mystery, dont they? This very effective Spanish-language one follows a married couple who are devastated when the body of their kidnapped 6-year-old daughter is found mutilated in a well. Five years later the mother, still unable to cope with her loss and addicted to tranquilizers, receives a mysterious phone call from who seems to be her daughter, still alive and in need of her help. Director Jaume Balagueró creates a convincing sense of uneasiness and dread throughout, making us feel right alongside its main character clinging to hope she thought had long gone. Its mystery plotting may be a little familiar but the proof is in the pudding with a creepy, atmospheric horror thatll keep your eyes glued to the screen. Available on US Netflix