Here are the facts. Means Girls was produced by Mark Waters in 2004. It was written by Tina Fey of Saturday Night Live fame. The cast included Lindsay Lohan, Rachel McAdams, Amanda Seyfried and Tina Fey.
The basic plot of the movie can be summarized by four points.
First, Lindsay Lohan as Cady Heron is the new girl in school. She was home-schooled so far by her parents who were on assignment as zooligist. She makes some friends, who are considered outcasts. Soon she learns about the mean girls.
Second, the most popular girls in school are called the "plastics." They are led by Rachel McAdams, who is appropriately named, Regina George. These are the mean girls of the movie.
Third, what complicates the plot is that Cady falls in love with Regina's ex-boyfriend Aaron (played by Jonathan Bennett). Regina is upset at this and win Aaron back, which causes there to be hostilities between Cady and Regina. To get back at Regina, Cady wages war. In the end, Cady becomes the queen bee and becomes ironically just like Regina. Absolute power corrupts absolutely, we might say.
Fourth, Regina, to get back at everyone, exposes the secrets of the class body and this causes a riot. There is a public apology that starts with Cady and soon things turn back to normal with one exception - no more mean girls.