In an alternative reality, lying – even the concept of a lie – does not even exist. Everyone, from politicians to advertisers to the man and woman on the street, speaks the truth and nothing but the truth with no thought of the consequences. But when a down-on-his-luck loser named Mark (Ricky Gervais) suddenly develops the ability to lie, he finds that dishonesty has its rewards. In a world where every word is assumed to be the absolute truth.