Kaitlin Olson Kaitlin Olson

There's a new girl on New Girl this season!

It's Always Sunny in Philadelphia star Kaitlin Olson has been cast in the recurring role of Ashley, reports the Hollywood Reporter.

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Ashley is Jess (Zooey Deschanel) and Cece's (Hannah Simone) former high school nemesis who is now engaged to Jess's father, played by Rob Reiner.

Olson joins previously announced Season 4 guest stars Jessica Biel and Reid Scott, and will first appear in Episode 3.

New Girl returns Tuesday Sept. 16 at 9/8c on Fox.

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