Flashback: Bradley Cooper Rocks Long Blonde Locks in First 'ET' Interview

Bradley Cooper turns the big 4-0 Monday -- with plenty of reason to celebrate!

His newest film American Sniper hits theaters everywhere Jan. 16 and is generating some much-warranted Oscar buzz, meaning Bradley could be an Oscar-nominee for his third year in a row.

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ET first met Bradley back in 2001, when the then-26-year-old actor landed his first major role in the hit TV series, Alias.

"It's like nothing I've ever seen on television – [I'm] totally blown away with it – it's hot, it's sexy, it's pumping, it's incredible."

Sporting long light-blonde locks, Bradley was happy to talk about his first big television role as Will Tippin, starring opposite Jennifer Garner and Michael Vartan.

"It's espionage, it's fast paced, but it's also about relationships," said Cooper of Alias. "Everybody's very ambiguous. You never really know who's the good guy and who's the bad guy and it constantly keeps you thinking."

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Cooper had a successful run on the series for three seasons before leaving the show in 2003 to pursue other projects. He landed comedic roles in Wedding Crashers and The Hangover, and would go on to star in Oscar-nominated roles in Silver Linings Playbook and American Hustle -- but it all started with Alias.

Watch this video to see light-blonde Bradley dishing on his first big role.

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For more flashbacks like this, check out 13-year-old Christian Bale's first interview below: