Forget Brooks Ayers — the ladies of The Real Housewives of Beverly Hills don’t mess around. During the upcoming reunion special, frenemies Lisa Rinna and Lisa Vanderpump duke it out over castmate Yolanda Foster’s health and season 6’s Munchausen-gate.

In a sneak peek of the drama to come on the hit Bravo show, things get so heated that Foster, 52, ends up walking off set after Rinna calls out Vanderpump for allegedly focusing the story line to revolve around Foster’s sickness.

“We’re at my birthday, and you came … I was thrilled to see you,” Rinna tells Foster, recalling her birthday episode at Il Cielo. “You came with no makeup. You left. [Vanderpump’s husband] Ken had said you looked terrible, and [my husband] Harry said, ‘You know what? That’s not OK. This woman is sick, and we need to stand by her.’”

The Vanderpump Rules star immediately came to her husband’s defense, refuting Rinna’s claims. 

“Ken didn’t say she looked terrible to her face … he was observing that she didn’t look good,” the businesswoman stated.

Rinna continued: “Harry said, ‘We need to support this woman whether she’s sick or not.’ … And you go, ‘There goes our ‘f--king’ story line.’”

After dropping the bomb, Foster starts to cry, and host Andy Cohen hands her a tissue.

Vanderpump attempts to deny the allegation, and a heated Rinna continues to put her on blast. 

“I’m not done!” the former soap star screams before dropping yet another bomb.

“I got a phone call from you, and you encouraged me to say ‘Munchausen,’” Rinna added before whipping out phone records. “I’m getting this out! You called me at home … I’ve got the phone records … 10 f--king phone calls! I’m sorry, you said you’ve never called me … [but] you encouraged me to say this.”

Watch the intense moment above!

The gripping three-part reunion for The Real Housewives of Beverly Hills begins on Bravo Tuesday, April 19, at 9 p.m. ET. 

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