Happy birthday to our girl crush, Rachel McAdams! The stunning actress turns 39 today and what better excuse to celebrate the star's big day than by looking back at her impressive career?

You might recall McAdams from the 2004 roles that made her famous: Regina George in Mean Girls and the romantic Allie in The Notebook, in which she shared screen time with co-star Ryan Gosling—who for a time became her boyfriend. See how much she's changed since those breakout roles by checking out her transformation through the years.

Credit: Dimitrios Kambouris/WireImage; Brian de Rivera Simon/Getty Images

What came next were roles in films including Wedding Crashers, Red Eye, The Family Stone, The Time Traveler's Wife, Sherlock Holmes, Morning Glory, Midnight in Paris, and many others. Through it all, McAdams portrayed all sorts of characters and she's proving there's no shortage of what roles she can take on.

McAdams appeared on Season 2 of the hit HBO seriesTrue Detective and the crime drama Spotlight starring opposite a cast including Mark Ruffalo, Michael Keaton, Liev Schreiber, John Slattery, and Stanley Tucci.

With upcoming roles in films like Game Night and Sherlock Holmes 3, we're sure to see a lot more of McAdams in the coming year.

Happy birthday, Rachel!