Ryan Phillippe turns 38 today -- and to celebrate, we're taking a look back at the film that helped make him a breakout star: "I Know What You Did Last Summer."
Though he first burst onto the scene playing gay teen Billy Douglas on "One Life to Live," the 1997 horror flick was one of Ryan's first major movie roles.
And he's not the only one whose career the success of the freaky flick helped!
Sarah Michelle Gellar and Jennifer Love Hewitt were hardly household names when the movie started filming in March 1997. The first episodes of "Buffy the Vampire Slayer" hadn't even aired yet when Gellar was cast and Hewitt was only known for her TV roles on "Kids Incorporated" and "Party of Five."
The movie also starred Freddie Prinze Jr., Anne Heche, Bridgette Wilson-Sampras and, randomly, Johnny Galecki.
Check out the gallery above to see how the cast has aged now that they're all in their late 30s -- plus, find out what they've all been up to in the past 15 years!
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