After breaking up with Mark Darcy five years earlier, Bridget Jones' happily-ever-after hasn't quite gone according to plan. Fortysomething and single again, she decides to focus on her job as top news producer and surround herself with old friends and new. For once, Bridget has everything completely under control. Then her love life takes a turn - while a weekend away at a music festival, she meets a dashing American named Jack, who is everything Mark is not, and spends a night with him. A week later, she runs into newly-separated Mark, and has a one-night dalliance. In an unlikely twist, she finds herself pregnant, but with one hitch - she's not sure of the identity of her baby's father - Mark or Jack.

Bridget Jones is an average woman struggling against her age, her weight, her job, her lack of a man, and her various imperfections. As a New Year's resolution, Bridget decides to take control of her life, starting by keeping a diary in which she will always tell the complete truth. The fireworks begin when her charming though disreputable boss takes an interest in the quirky Miss Jones. Thrown into the mix are Bridget's band of slightly eccentric friends and a rather disagreeable acquaintance into whom Bridget cannot seem to stop running or help finding quietly attractive.