"Real Housewives of Beverly Hills" star Kim Richards has finally admitted why she went to rehab.
In a just-released promo for the show's 3-part reunion special, Richards is seen having a one-on-one sit down with Andy Cohen -- who asks "Can you tell us what you sought treatment for?"
Her reply: "I'm an alcoholic."
The reveal is only one of many big moments in the sure-to-be-explosive special, which includes confrontations between Lisa Vanderpump and Adrienne Maloof as well as Taylor Armstrong and Brandi Glanville.
Part 1 airs January 30, Part 2 on February 6 and Part 3, which includes the Kim one-on-one, airs February 13.