That chemistry! On June 25, 2004, little known actors Ryan Gosling and Rachel McAdams were suddenly catapulted into the spotlight after the film adaptation of Nicholas Sparks' The Notebook hit theaters. Ten years later, the two stars—who dated in between—have emerged as mega movie stars, thanks to their palpable onscreen romance in the drama.

The process behind finding the film's leading lady was extensive, with director Nick Cassavetes and Gosling screening actresses far and wide in search of the perfect fit. "Some of them were really, really great," Cassavetes recalled in a featurette about the 9 "very well-known" actresses who auditioned for the role. "When Miss McAdams came in and read, it was apparent that she was 'the one.'"

McAdams' agent arranged for her audition in The Notebook, and Cassavetes said, at the time, "I didn't know who she was." For her screening, the up-and-coming Mean Girls star—a "last-minute addition"—read lines for the scene where Allie tells Noah she's leaving to return to her fiance. "They were wonderful and they were very irresponsible," McAdams, clearly in character, says to Gosling who reads his lines off to the side.

"I read the script the night before and bawled my eyes out," McAdams, now 35, confessed in the featurette. "It was the best audition experience I've ever had."

Gosling, now 33, added, "She left, and Nick and I just gave each other a hug."

Watch McAdams' amazing audition above!