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 is produced by Saturday Night Live (SNL) creator Lorne Michaels. Screenwriter and co-star of the film, Tina Fey, was a longtime castmember and writer for SNL. The film also features appearances from SNL cast members Tim Meadows, Ana Gasteyer and Amy Poehler.
The exterior high school scenes were shot at Etobicoke Collegiate Institute in Etobicoke in the historic Islington neighbourhood in Toronto's west end.