Mary-Kate Olsen may be on the outs with her sister Ashley, but at least the pint-sized mogul’s still got a vibrant acting career to keep her busy. MK is currently taping a guest spot for an episode of ABC’s Samantha Who?, scheduled to air on the ratings winner this Fall.

ABC has just confirmed that Mary-Kate is shooting an episode of the divine, good-versus-evil comedy this week, playing a character whom Samantha tries to “save,” TV insider tell E! News.

And Mary-Kate’s already receiving praise from several spies on the set of Samantha Who?:

“She started today, and she’s terrific.”