At 5-foot-1, Nicole Richie is not what you would call physically imposing. But she'll still put a scare into "Chuck" superagent Yvonne Strahovski come fall.

Richie has landed a guest-starring role on the NBC series, playing Sarah's (Strahovski) former high-school nemesis. "Chuck" is scheduled to return to NBC in late September; an airdate for Richie's episode hasn't been set.

"Nicole auditioned for the part and was very funny," executive producer Josh Schwartz says. "This role is a great opportunity for her to show off her comedic skills and be diabolically evil and kick some butt. It's going to be really fun."

Richie will play a "snarky and spiteful" girl who made sport of picking on Sarah in high school. The two cross paths again when Sarah has to attend her 10-year reunion as part of a mission, with Chuck (Zachary Levi) as her date.

Richie is best known for starring with Paris Hilton on "The Simple Life" and her countless appearances in the celeb media for reasons both good (the birth of her daughter, Harlow, in January) and bad (a 2006 DUI arrest). She's made a handful of guest appearances on scripted shows too, including "American Dreams" and "8 Simple Rules."