"The Hills" Cast -- Where Are They Now?!

It's hard to believe it's been 10 years since "The Hills" made its big debut on MTV.

To celebrate the milestone, the cast is revealing some big secrets about the uber-popular reality series.

Lauren Conrad is the first to admit that her relationship with former bestie Heidi Montag is rocky, so fans were shocked to see her at Montag's wedding to Spencer Pratt.

But, it seems, she was just trying to get out of there ... when there was a major electrical mishap!

"The power went out, the generator went out and I said, 'I need to leave!'" the reality star says in the new issue of Us Weekly. "And [producers] wouldn't let me leave! They literally locked me in the basement with two security guards and wouldn't let me leave! And I was like, 'You can't keep me here!' I was throwing a fit!"

For his part, producer Adam DiVello says Conrad "might have felt locked in, but she was not."

Two hours later, it was finally time to film the wedding. As soon as the ceremony ended, Conrad made her exit.

"At that point, this wasn't really my life anymore, and I left out the [church's] side door, so that's why in the final scene, I'm not leaving with everyone else — I'm taking a side exit out because I had a car waiting, and I needed to leave!" she says.

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All the bad blood between LC and Heidi started because of a rumored sex tape with Lauren's ex, Jason Wahler.

The resident bad boy admits that he was surprised by the sex tape story line.

"[The sex tape story] really came out of left field," he tells the mag. "Lauren and I talked, even though we were separated. I was like, 'Did you put a camera in the bedroom that I didn't know about?'"

"I didn't start [the rumors]," Pratt chimes in. "But it wasn't a rumor, because a rumor implies that something is not true."

Sounds like these guys still can't agree on what really happened!

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Another major story was Kristin Cavallari's reported drug problem, which was highlighted during a group trip.

"One of the producers bribed Lo [Bosworth], Audrina [Patridge] and Stephanie [Pratt] and promised them he would buy them presents if they called me out on camera for doing drugs," Cavallari reveals. "Then Lo said, 'Can I have a Birkin bag?' And he said yes. She never ended up getting the Birkin. You need to get that s--t in writing! It ended with all of the girls and I, our managers, agents, producers and lawyers in a room. I was told it wasn't going to be a story line, and sure enough, it was."

"Listen, I definitely had fun in my early twenties, but I was never out of control," she declares.

To get even more dirty details about the show, pick up the latest issue of Us Weekly, on stands now.

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