Lawyer Elle Woods (REESE WITHERSPOON) is fresh out of Harvard Law School and is planning her upcoming nuptials to Professor Emmett Richmond (LUKE WILSON). A flighty but intelligent blonde, she wants to invite the mother of her dog, Bruiser, to the wedding, but doesn't know her whereabouts. A private investigator eventually leads Elle to an animal research lab where the pooch is being used for cosmetic testing.
Horrified at the discovery, Elle wants her law firm to do something about it, but since their client owns the lab and they don't take her seriously, she ends up being fired. With encouragement from Emmett and her dimwitted hairdresser friend, Paulette Parcelle (JENNIFER COOLIDGE), Elle decides to head to Washington, D.C. to change the law.
There, she gets a job as a legislative assistant to Congresswoman Rudd (SALLY FIELD) and meets her new co-workers including Chief of Staff Grace Rossiter (REGINA KING) as well as Reena Gulani (MARY LYNN RAJSKUB) and Timothy McGinn (J. BARTON), none of whom take her, her appearance or perky attitude seriously.
Nevertheless, she then sets out to convince Committee Chairwoman Libby Hauser (DANA IVEY) and conservative Member Stanford Marks (BRUCE McGILL) to join her cause. They're initially reluctant, but her charm, perseverance and creativity in breaking down their resistance eventually wins them over. They then join her in supporting "Bruiser's Bill" which will outlaw animal testing for cosmetic purposes.
Yet, when an unexpected obstacle threatens to derail the bill, Elle calls in Paulette and her friends
Margot (JESSICA CAUFFIEL) and Serena (ALANNA UBACH) to help. With the aid of wise doorman Sid Post (BOB NEWHART), they set out to push their bill through Congress.