'The Notebook' Casting Director on Britney Spears' 'Unbelievable' Chemistry With Ryan Gosling (Exclusive)

Matthew Barry shared the unreleased footage of Spears' 2002 audition and talks his reaction.

Matthew Barry saw Britney Spears' audition for The Notebook in 2002 with his own eyes, and the casting director is still amazed. 

"Britney Spears was unbelievable. She was absolutely unbelievable," Barry tells ET's Kevin Frazier of the pop star's audition for the role of Allie Hamilton. "Britney came in and blew us all away."

On Monday, The Daily Mail released the first-ever footage from the audition. In the 2 1/2-minute clip, a then 21-year-old Spears wears a simple white lace top as she stands in front of Ryan Gosling -- who is off-screen -- and a camera. 

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Spears becomes emotional on queue as she recites Allie's monologue where she is faced with the decision to choose between Noah (Gosling) and her wealthy fiancé. 

In a heart-wrenching moment, Spears begins to cry as she delivers the lines, "I prayed for you to die in the war, really. Well, not die. I would have felt completely horrible if you would die. But I kinda didn’t want you to be alive anymore because I couldn't bear the thought of you being with somebody else, or of us never seeing each other again. So I gotta go, OK?"

"I'm glad her fans have now gotten a chance to finally see it. And I just honestly, I think she should really go back to it," Barry says about the footage coming to light for her fans to see. 

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Though the clip doesn't show Spears speaking to Gosling, who went on to star in the film alongside Rachel McAdams, the chemistry was there. 

"Ryan and Britney were very professional," he says about the moment the two Mickey Mouse Club co-stars were reunited during the chemistry test. "If you've ever met Nick Cassavetes, he can be very intimidating at 6 foot 5. Ryan was really cool, he allowed Britney the time to meet with Nick to discuss the role, to discuss the character. And I think once it was all over, then it was, like, reunion time."

For Barry, he wasn't surprised at the amount of emotion the "Oops I Did It Again" singer displayed. 

"We didn't know what was going on at the time with her and Justin Timberlake. So I think that she absolutely tapped into what was going on at the time," he says about the audition, which Spears claims came after their highly publicized breakup.

New Line Cinema

"Again we didn't know. I think she definitely tapped into her emotional depth and brought it out. She showed us she was raw, she was emotional, she was fantastic. She laid it all out on the line," he adds.

Barry reveals that Spears was very close to getting the role. However, the filmmakers were blown away after seeing McAdams' audition. 

New Line Cinema

"Rachel blew us away," he tells ET. "Britney came in, and then Rachel came in, I think, shortly afterwards, and just destroyed us. It was a very, very hard toss-up between the two of them. There was lots of arguing as there are in any film that ever gets made. I think the studio probably wanted Britney for obvious reasons. But Rachel, it was her role." 

In her memoir, The Woman in Me, Spears gets candid about her lack of desire to act and why she was fine not landing the role.

"If I had, instead of working on my album In the Zone, I'd have been acting like a 1940s heiress day and night," she writes, according to The Daily Mail. "I hope I never get close to that occupational hazard again. Living that way, being half yourself and half a fictional character, is messed up. After a while you don't know what's real anymore."

While Barry respects Spears' decision to give up acting, he would tell her to come back if he had the chance.

"Come back, come back. We need you," he tells ET. "We all need you and come train with me."

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