EXCLUSIVE: 'Vanderpump Rules' Stars Katie, Stassi and Kristen Call Season 5 'Darwinism at Its Finest'

ET sat down with the cast at SUR Lounge.

Everyone makes it out alive this season on Vanderpump Rules… but that doesn’t mean they survive SUR.

“Let's call it survival of the fittest,” Katie Maloney tells ET.

“Darwinism at its finest,” Stassi Schroeder says.

The ladies and their co-star, Kristen Doute, recently dished details about season five of the Bravo hit with ET at SUR Lounge in West Hollywood. They say there might be some truth to those rumors Lala Kent, the show’s de facto villain this year, started herself about leaving the series. In July, she tweeted -- then deleted -- that she had decided to “part ways” with the show.

“That’s what she said,” Katie teases.

MORE: A Day in the Life of Stassi Schroeder

The new season is only a few episodes in, but already Lala has had multiple explosive arguments with the “OG” crew -- those who have been around since season one. Kristen admits the only way to survive this group is to join it or, at the very least, stay friendly with her, Katie and Stassi.

“It's so easy,” Stassi chimes in. “Why don't people learn? When are people going to learn?”

Well, it’s not exactly easy. Stassi, Katie and Kristen have quite the history together, their friendship falling apart about two years ago following a series of betrayals that’s, honestly, too long to list. When the cast sat down this year, they admitted they never expected to be this friendly again.

“I was hoping for it,” Kristen confesses.

“I have a voodoo doll,” Stassi jokes. “So [Katie] had no choice than to be friends with me again.”

WATCH: Lisa Vanderpump Takes on Those Kristen Doute, Brittany Cartwright Hook-Up Rumors

In reality, the group attributes reconnecting to their shared history -- the good and the bad.

“It's history from before the show, building the show and this sort of empire that Lisa [Vanderpump] has created for us and with us,” Kristen says. “You go through things together that no one else goes through. It's just... it's almost unexplainable.”

“It’s a special bond for sure,” Katie adds. “People are always like, 'But you do the worst things to each other! You screw each other over in the most extreme ways... Like, how do you [move past it]?’ I don't really have a clear answer for that, but I do think it just speaks volumes how much we do value, and really do care for, each other.”

“I'm so proud of our group of friends,” Stassi continues. “If you can overcome some really dark, dark things, you only turn out to be better friends after that. And I feel like we have this wolf pack mentality now, that's really nice and it feels safe and comforting. We won't let anyone hurt each other. Only we can hurt each other!”

WATCH: Ariana Madix and Tom Sandoval Talk Lowering Their Standards for Reality TV

From the looks of the season’s teaser trailer, there will be some pain caused this year -- but also more makeups. Katie, Stassi and Kristen note there will be some “shifts” in the group.

“Even the ‘OG’ dynamic, mine and [boyfriend Brian] Carter's relationship with Tom [Sandoval] and Ariana [Madix] is an interesting one to watch,” Kristen promises. “Having to be around each other and the way that that works out is interesting.”

“I think there's just a lot of nuance, too,” Katie shares. “I was happy to see [the shifts], and I think that people who have watched the show since the beginning will be like, yay!”

Vanderpump Rules
airs Monday nights at 9 p.m. ET on Bravo. While you wait for the next episode, check out what Katie and Scheana Shay had to say about their co-stars last year when they played "SUR-perlatives."