Mary Cosby — who married her step-grandfather — thinks her “Real Housewives of Salt Lake City” co-star Heather Gay “looks inbred.”
At the end of the shocking new Season 4 trailer, which included many co-stars hurling insults at one another, Gay asks Cosby during a one-on-one conversation, “Do you think I look inbred?”
“I do,” Cosby confidently says without a second thought.
Gay appears taken aback and shocked as she gapes at Cosb – who famously married her step-grandfather after her grandmother died and encouraged her to do so.
Page Six previously broke the news that Cosby – who quit the show after Season 2 – would be returning to “RHOSLC” in a “friend of” role as Meredith Marks’ friend.
“Here I am!” Cosby says as she walks into Marks’ jewelry store in Park City, Utah.
The trailer cuts to Cosby, 50, saying in her confessional, “Somebody rescue me quick!”
Cosby seems to waste no time at all getting comfortable with the group, bluntly stating, “Somebody farted,” during another group scene.
Elsewhere in the teaser, Cosby gets lunch with Whitney Rose and tells her, “Pipe down, bobblehead.”
Finally, the group returns to their sprinter van roots where Cosby sits next to Lisa Barlow and asks her, “Do you have a mute button?”
“No, I don’t. I’m on play all the time,” Barlow, 48, shoots back.
A source told Page Six in February that “Mary wanted to come back,” but she struggled “with a lot of trauma after Season 2.”
She and Marks, 51, were able to “re-establish a connection” prior to cameras filming Season 4 of the hit Bravo show.
The bombshell trailer teases several other feuds among the ever-evolving alliances and friendships in the cast – which also includes newcomer Monica Garcia and “friend”-turned-full-time “Housewife” Angie Katsanevas.
Notably, Season 4 marks the first season without Jen Shah – whom is currently serving her six-year prison sentence at Bryan Federal Prison Camp in Texas for defrauding thousands of people in a telemarketing scheme.
“For three years, we were tormented, brutalized and lived in fear, and it’s time to end it,” Gay, 49, proclaims at a group dinner.
The trailer also teases several other storylines – including marital problems between Whitney, 36, and Justin Rose, 54,
“To see your wedding ring in the drawer every day that hurts me,” Whitney tells Justin while wiping away her tears.
Barlow and Gay also seem to disagree over Barlow sending her oldest son, Jack, on a mission through the Mormon church.
“The doctrine is problematic,” Gay tells Barlow before Barlow storms off and tells her, “I don’t wanna talk about Jack’s mission.”
There’s also rumblings of marital issues between Katsanevas and her husband, Shawn Trujillo.
For more Page Six reality TV updates
“I stood up for our marriage and for our family unit,” Katsanevas says to her tearful and emotional husband.
Meanwhile, Marks seems to be back to her true form of engaging with her other castmates and participating in several intense conversations throughout the trailer.
“I am getting really f–king pissed off!” Marks screams during a boat trip while walking away from the group.
The trailer ends with Gay screaming to someone at a group dinner, “You are a f–king bully and a f–king troll! Pack your bags and go.”
Season 5 of “The Real Housewives of Salt Lake City” premieres Tuesday, Sept. 5 at 9 p.m. ET on Bravo.