Watch The Dramatic ‘Vanderpump Rules’ Season Four Reunion Trailer HERE!

The Vanderpump Rules season four reunion special is going to be so dramatic that is going to leave you VanderSHOCKED! For this year's reunion, Andy Cohen and SUR owner Lisa Vanderpump take a look back at Ariana Madix, James Kennedy, Jax Taylor, Katie Maloney, Kristen Doute, Scheana Marie Shay, Tom Sandoval and Tom Schwartz's most memorable moments.

Also appearing on the reunion special are newbie Lala Kent, Jax Taylor's girlfriend Brittany Cartwright and original cast member Stassi Schroeder.

In this Us Weekly exclusive preview, Lisa Vanderpump is seen saying to one of her fellow cast members, "I was furious at him for lying to her."

The Real Housewives of Beverly Hills star also has a intense exchange with Stassi Schroeder, as the two have clashed ever since the former SURver returned to the series midway through the season. Their issues stem from Vanderpump paying off Schroeder's ex after he threatened to release a sex tape.

"You and Ken [Todd] had gone to my parents and told us, 'You owe me 900 dollars,'" Schroeder, 27, says in the sneak peek. Vanderpump fires back, "Really? I was saving your ass."

James Kennedy also threatens to slug Jax Taylor in the throat. The three-part Vanderpump Rules Season 4 reunion kicks off on Monday, March 21. Watch the official trailer below!