Real Housewives of Beverly Hills star Denise Richards is reportedly sick and tired of castmate Lisa Rinna's antics on the show, Rinna's many attempts to whip up drama to keep herself relevant on the Bravo franchise.

 "Behind the scenes, Lisa Rinna is continuing to be the instigator and continuously stir the pot for maximum drama. Rinna does this to make herself relevant and maintaining job security," an insider told US Weekly.

"Denise has had enough of Rinna's constant meddling and passive-aggressive behavior, especially with social media. Denise and Rinna are headed toward a showdown on camera, which is what Rinna has wanted. Rinna is going to be exposed and held accountable; if Denise is the one to do it, bring it on," the source added.

Rumors swirled last week that Denise had quit the show, but sources close to the star, including Camille Grammer, have since shot down those rumors.