Donna (Kimberly Quinn): Now
Kimberly Pita Quinn started her acting career in 1995 with a guest star appearance on the Fox sitcom, Partners.
Since then, she’s appeared in shows like NYPD Blue and House M.D. before she landed her role on Two and a Half Men.
After her part as Donna, she’s appeared in CSI: NY, before landing the main role of Gretchen in the FX network’s 2010 crime comedy drama, Terriers.
Since then, she’s made appearances in Twisted, Grey’s Anatomy and Gypsy.
Shannon (Tammy Lauren): Then
We meet the character of Shannon, portrayed by Tammy Lauren, in the fourth season episode, “Aunt Myra Doesn’t Pee a Lot.”
Alan meets Shannon at Herb and Judith’s wedding. She’s Herb’s ex-fiancée, and in an attempt to make Herb jealous at his wedding, she tried to hook up with Alan in a broom closet.
Alan isn’t comfortable with this, but is willing to pretend they’ve hooked up in order to achieve the same effect.