A man traveling through rural Spain in search of the town where his girlfriend awaits becomes ensnared in a surreal waking nightmare in director Gonzalo Lopez-Gallego's intricate thriller. Quim (Leonardo Sbaraglia) was on his way to visit his girlfriend when he stopped off at an isolated gas station for some fuel and a quick trip to the restroom. But the men's toilet is out of order, and in his haste Quim ducks into the ladies room. Upon exiting, Quim crosses paths with a mysterious beauty named Bea (Maria Valverde). The sexual tension is as immediate as it is undeniable, and the two strangers engage in some explosive, anonymous sex right there on the bathroom sink. Recognizing the opportunity in the moment, Bea absconds with Quim's wallet and lucky lighter. Of course, it isn't long before Quim realizes what's happened, and when he subsequently spies Bea's car sitting abandoned on an unmarked road, it seems like the perfect opportunity to retrieve his personal property.

Suddenly, out of the quiet country air, a shot rings out and Quim is wounded. As Quim ducks for cover nearby, he sees that Bea is also hiding from the unseen sniper. Eventually the frightened pair manages to escape their assassin's bullets and make their way to the local police. Much to their surprise, the authorities not only voice doubt about the existence of the mysterious sniper, but also cast a troublingly suspicious eye on them. Regardless of their initial skepticism, however, the police are about to discover that anyone who dares venture out on this mountainside is immediately marked for death.