Rachel McAdams has been in all kinds of movies, from romances to thrillers, and in them she's pretty much always playing a sweetheart girl-next-door type you can't help but love. It makes sense, since Rachel strikes us as a pretty nice girl in real life, too.

But ironicallly enough, her most beloved character is her cruelest ― Mean Girls' Regina George, the character she's still best known for. Almost no one in the history of cinema has portrayed a high school Queen Bee with such chilling accuracy.

Tomorrow is celebrate Rachel’s 34^th birthday, so we thought we’d celebrate her post-Mean Girls movies and ask that crucial question, "WWRGD?" ("What Would Regina George Do?") Because we’re pretty sure crafty, vindictive Regina would have found her way through these dilemmas much more efficiently than these other characters she's played.