The CW series' spokeswoman, Melissa Burton, says the 21-year-old singer and actress will guest-star next season as "a movie star looking for a typical college experience."
Duff's character, named Olivia Burke, enrolls at New York University and becomes roommates with "Gossip Girl" hipster Vanessa, portrayed by Jessica Szohr (ZOR).
Oh, what a tangled web: Burton says Olivia will spark a romance with aspiring novelist Dan, played by Penn Badgley. As fans know, Vanessa used to have eyes for Dan — then they dated other people.
Duff begins her "Gossip" arc on Oct. 5.
Season three premieres Sept. 14, as the prep kids head off to college.
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