In Los Angeles, California Fletcher Reede (Jim Carrey) is a career-focused lawyer and divorced father. He loves spending time with his young son Max (Justin Cooper); they often play a game where Fletcher makes his hand into "the Claw" and pretends to chase Max with it. But Fletcher has a habit of giving precedence to his job, breaking promises to Max and his ex-wife Audrey (Maura Tierney), and then lying about the reasons. Fletcher's compulsive lying has also built him a reputation as one of the best defense lawyers in the state of California as he is climbing the ladder in the firm for which he works. Ultimately, Fletcher misses his son's fifth birthday party because he is having sex with his boss Miranda (Amanda Donohoe). Max makes a birthday wish that his father would be unable to tell a lie for an entire day; a wish that immediately becomes true.