Annabelle Fritton unwillingly transfers to St Trinian's from the distinguished
Cheltenham Ladies' College at the request of her father, Carnaby Fritton. She is taken around the school by Kelly Jones, the
head girl, who introduces her to the various cliques within the school; Chavs, Posh Totty, Geeks, Emos and First Years. Annabelle is harassed and pranked by the girls while in the shower and a video of her running around the school naked and wet is
broadcast live on the internet. After a phone argument with her father she is drafted to the hockey team when she hits her phone with her hockey stick, smashing a statue. The girls of St Trinian's are involved in business with
spiv Flash Harry, who pays them to make cheap vodka. Flash is attracted to Kelly, who initially turns him down. Meanwhile, Miss Dickinson joins the school as the new English teacher where she is immediately confronted with the school's anarchic system. The Cheltenham Ladies' College hockey team arrive at St Trinian's, along with Education Minister Geoffrey Thwaites, who shares romantic history with the headmistress of St Trinian's, Camilla Fritton. Annabelle is forced to face her former bullies, including captain Verity Thwaites. The hockey match is violent, ending in Kelly shooting a winning goal for St Trinian's, and Annabelle begins to fit in with the other girls. As the match is being played, Thwaites inspects the school, finding the illegal vodka-making business and the chatline being run by the Posh Totty clique. The following morning, a banker arrives at the school and serves Camilla with a foreclosure notice, as the school owes the bank in excess of £500,000 and has ignored six previous final demands. A subsequent meeting between Camilla and Carnaby is watched by the girls using hidden cameras, in which Carnaby confesses his distaste towards his daughter. Annabelle is left upset, despite Camilla defending her. Carnaby encourages Camilla to turn the school into a boutique hotel, which Camilla vehemently refuses. Kelly and Flash work with the students to devise a plan to save the school. They must get into the final of
School Challenge, a TV quiz show held in the
National Gallery in London, as a cover for stealing
Vermeer's
Girl With a Pearl Earring. Chelsea, Peaches and Chloe, the Posh Totty clique, are chosen as the
School Challenge Team. By cheating in every round, they make it to the grand final. During this, Annabelle integrates with her peers and is given a makeover. As the final is being filmed, Kelly, Taylor and Andrea plot to steal the painting, with help from the Geeks, Annabelle and Camilla herself. During the final against Cheltenham Ladies' College, Thwaites suspects their cheating and cuts the microphone feeding the answers. However, Camilla inebriates Thwaites until he's unconscious and Annabelle incapacitates Verity. Chelsea, with the encouragement of Miss Dickinson, delivers the winning answer. Camilla helps Kelly, Taylor and Andrea escape with the painting as the school celebrates their victory. Camilla paints an exact copy of the painting and has Flash, posing as a German art dealer, sell it to Carnaby in a black market deal. The school then receives a further £50,000 reward for returning the real painting to the National Gallery. The loans are able to be repaid and the school is saved. ==Cast and characters==