'Hills' Buzz Moment #1: Lauren Conrad Leaves, Kristin Cavallari Enters

When LC decided to leave 'The Hills' behind, Cavallari was there to keep the drama alive.

Over the years fans have watched Lauren Conrad grow up as the main protagonist on [url id="http://www.mtv.com/shows/the_hills/season_6/series.jhtml"]"The Hills."[/url]

We were there when she graduated from high school on "Laguna Beach" and when she decided to move to L.A. to study fashion in college.

We saw her first love with Jason Wahler and her first heartbreak. "I don't want you out of my life, but I can't be normal with you," she later told Wahler when they decided to end their relationship.

Fans also got to see the sweet beginning and bitter end to the friendship with Heidi Montag. "We don't really have a relationship," LC later said about Heidi. "We're friendly with each other. I don't have a problem with her, but, you know, we're not great friends."

Yet when Lauren decided to leave the show in 2009, viewers couldn't imagine "The Hills" without her — until it was announced that a familiar face and her former "Laguna Beach" frenemy was moving back in. Kristin Cavallari immediately caused a splash in "The Hills" reminding us all why we loved to hate her.

"It's almost like going home. It's really comfortable," Cavallari said

of joining the show in its fifth season. "I know what to expect going into it, so I think I'm just more excited than anything."

So with "The Hills" coming to a close this season, Cavallari is now, once again, center stage, which means we're sure to see a whole lot of drama. But we'll still keep our fingers crossed that Lauren makes a return, even if she's hinted to the fact that she's already moved on.

"I'm not planning on it," she said last year. "I'm happy with the time I walked away, and I think that from now on, they're going to pick it up and do a great show. But I think that my time on it is done."

What are some of your favorite "Hills" moments? Let us know in the comments below!

"The Hills: Final Season" premieres tonight at 10 p.m. ET/PT followed by "The City" at 10:30 p.m. ET/PT on MTV.