Mean Girls

Mean Girls is a 2004 American teen comedy film directed by Mark Waters. The screenplay was written by Tina Fey and is based in part on the non-fiction book Queen Bees and Wannabes by Rosalind Wiseman, which describes how female high school social cliques operate and the effect they can have on girls. The film stars Lindsay Lohan and features a supporting cast of Rachel McAdams, Lacey Chabert, Amanda Seyfried (in her film debut), and Lizzy Caplan. The film was produced by Saturday Night Live (SNL) creator Lorne Michaels. Screenwriter and co-star of the film, Tina Fey, was a long-term cast member and writer for SNL. The film also features appearances from SNL cast members Tim Meadows, Ana Gasteyer, and Amy Poehler. This film marks Lohan's second collaboration with director Mark Waters, the first one being Freaky Friday (2003).
The film received generally positive reviews from critics and was a box office success, grossing $129,042,871 worldwide.

STORY LINE
Cady Heron (Lindsay Lohan) is the 16-year-old homeschooled daughter of zoologist parents (Ana Gasteyer and Neil Flynn). They have returned to the United States after a 12-year research trip in Africa, settling in Illinois. New classmates Janis (Lizzy Caplan) and Damien (Daniel Franzese) warn Cady to avoid the high school's most exclusive clique, the Plastics, the girls led by queen bee Regina George (Rachel McAdams). The Plastics take an interest in Cady, inviting her to sit with them at lunch and shop with them after school. Seeing this, Janis hatches a plan of revenge against Regina, using Cady as infiltrator.
Cady soon learns about Regina's "Burn Book", a notebook filled with rumors, secrets, and gossip about the other girls and teachers. Cady also falls in love with Regina's ex-boyfriend, Aaron Samuels (Jonathan Bennett), whom a jealous Regina steals back at a Halloween party. Cady continues with Janis's plan to cut off Regina's "resources," separating her from Aaron, destroying her beauty, and turning Regina's fellow Plastics, insecure rich girl Gretchen Wieners (Lacey Chabert) and sweet but ditzy Karen Smith (Amanda Seyfried), against her. In the process, Cady remakes herself in Regina's image, becoming spiteful and superficial and abandoning Janis and Damian.
Regina responds by spreading around the contents of her Burn Book, quickly inciting a riot. To avoid suspicion, Regina inserts a fake libel of herself in the book in order to blame Cady, Gretchen, and Karen, the only female students not mentioned in the book. Principal Ron Duvall (Tim Meadows) soon quells the riot, and math teacher Ms. Sharon Norbury (Tina Fey), whom the Burn Book slandered as a drug dealer, makes the girls involved in the plot confess and apologize to the other students and teachers. When Janis's turn comes, Regina makes an insulting joke about her sexuality, at which the crowd laughs. Janis retaliates by confessing her plan to destroy Regina with Cady's help, and openly mocks Regina with the support of the entire school. Pursued by an apologetic Cady, Regina storms out and gets hit by a school bus, breaking her spine.
Without friends, shunned by Aaron, and distrusted by everyone, Cady takes full blame for the Burn Book. Her guilt soon dissolves, and she returns to her old personality. As part of her punishment and reformation, she joins the Mathletes in their competition. There, while competing against an unattractive girl, Cady realizes that mocking the girl's appearance would not stop the girl from beating her. At the Spring Fling dance, Cady is elected Queen, but declares that all her classmates are wonderful in their own way, whereupon she breaks her tiara and distributes the pieces. Cady makes amends with Janis and Damian, reconciles with Aaron, and reaches a truce with the Plastics.
By the start of the new school year, the Plastics have disbanded. Regina joins the lacrosse team, Karen becomes the school weather girl, Gretchen joins the "Cool Asians", Aaron graduates from high school and attends Northwestern University, Janis and Kevin begin dating, and Cady declares that she is now "an actual human being". Damien witnesses the new Junior Plastics walking by, but they are immediately hit by a bus. It turns out, however, that this was only a humorous figment of Cady's imagination.