Handsome 25-year-old César (Eduardo Noriega) has it all--a successful career, expensive cars, a swank bachelor's pad, and an endless string of beautiful and willing women. Unfortunately, he can't get rid of his latest conquest, Nuria (Najwa Nimri) soon enough. When she crashes his birthday party, César uses his best friend Pelayo's stunningly attractive girlfriend, Sofia (Penélope Cruz), as a means to her. The next morning, Nuria is waiting in her car outside his apartment and manages to coax him into the vehicle. The next thing César knows, he's wearing a mask to conceal a horrible disfiguration while being interrogated in a prison held on a murder charge. Alejandro Amenábar's thriller distorts both the viewer's and César's perception of reality with a series of mind-bending plot twists, ensuring that this intriguing Spanish production will keep you guessing until its final moments.