Back in May 2008, Lauren Conrad and Heidi Montag had already had a major falling-out and were no longer on speaking terms. So when Rolling Stone called and wanted to put all the stars of "The Hills" on the cover of the magazine, the show's producers knew it would take some work to get the onetime pals in the same room again to join Whitney Port and Audrina Patridge for the scantily clad photo shoot.

"You know, MTV press called us up and they said that Rolling Stone is interested in doing a cover for 'The Hills.' So, of course, you know, it's the best call you can get," show creator Adam DiVello recalled in an outtake from [article id="1643389"]"The Hills: Revealed."[/article] "I mean, for me anyway, every cover to me is iconic. I love the magazine, and the thought of a show that I created getting on the cover of Rolling Stone to me was an end all, be all."

The cover came with one big caveat: "All four girls, bottom line, no ifs, ands or buts," DiVello recalled. "When you've got Rolling Stone calling [and] they want your cast on the cover of the magazine, but two of your castmembers don't want to be together in the same room -- namely Lauren and Heidi -- it seemed like it was never going to happen. I mean, there was a time when we thought, 'This is not going to happen,' because we were not going to get them together."

But it seemed like the magazine-cover gods were shining on them, and the shoot came together. "You get to the bottom of it and figure out how to make it happen," DiVello said. "And luckily, we pulled it off."

Are you excited for "The Hills" season finale on Tuesday? Tell us in the comments!

Join MTVNews.com on Tuesday, July 13, at 8 p.m. ET for a live stream from the red carpet of Hollywood's Roosevelt Hotel, where the stars will gather for "The Hills Live: A Hollywood Ending." Then tune in for the series finale at 10 p.m. ET on MTV and "The Hills Live: A Hollywood Ending After Show" at 11.