Bridget, a single woman in her early thirties, resolves to take control of her life by keeping a diary and vowing to improve herself. She aims to lose weight, stop smoking and drinking, and find a suitable boyfriend. Bridget’s romantic life becomes complicated when she starts dating her charming but unreliable boss, Daniel Cleaver. Meanwhile, she also grapples with feelings for the seemingly uptight Mark Darcy, a childhood acquaintance reintroduced to her during a New Year's party. As she navigates these relationships, she experiences a lot of humorous and awkward situations while trying to maintain her resolutions.

Midway through, Bridget finds herself caught between the affections of Daniel and Mark. Her career also sees its share of ups and downs as she attempts to prove herself professionally amid personal chaos. The funny and heartfelt journey captures her struggles and triumphs as she endeavors to make sense of her love life and self-worth. Bridget's relationships and the choices she makes lead her to unexpected realizations and developments. The story’s blend of romance, comedy, and self-discovery paints a vivid picture of her quest to find happiness and fulfillment.