ET First Look: Jessica Biel looks stunning on the cover of the February issue of Vogue, on newsstands January 26, and in the magazine the 'Valentine's Day' star reveals her regrets about posing nearly naked when she was 18!

Watch Jessica behind the scenes of her Malibu photo shoot!

"I really wanted to go to college, and it all kind of happened at the same time," she says about posing for Gear magazine, which freed her from her "7th Heaven" contract after the show's fourth season. "I did this photo shoot. The photo shoot came out. It was terribly embarrassing. I had to apologize to everybody, including my parents. It was a big learning experience -- learning how to have boundaries and how to say no."

In Jessica's candid interview with Vogue contributing editor Jonathan Van Meter, she also explains why she won't discuss her relationship with beau Justin Timberlake, saying, "It's the most precious thing I have in my life, and I care about it so much that I don't care about what anyone says or thinks. … It's mine. And I really like that about it."

For her photo shoot, Vogue photographer Mario Testino captures two sides of Jessica, going for a bombshell retro look in an Oscar de la Renta gown and as a natural beauty in Ralph Lauren Collection overalls. The second shoot found Jessica keeping company with some wily farm animals, including a runaway tortoise and a rooster that couldn't quite "hold it" while sitting on her shoulder!

Watch ET for more with Jessica!

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