NBC’s returning drama Chuck will get a new cast member this fall, when Nicole Richie joins the cast for one episode as Special Agent Sarah Walker’s high school nemisis.

Richie will guest star as the snarky and spiteful girl who tortured Sarah in school. Now Sarah must face her fears when she’s forced to attend her 10-year high school reunion.

"Nicole auditioned for the part and was very funny," said executive producer Josh Schwartz. "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."

This will be Richie’s first guest role since giving birth to her daughter Harlow. In addition to co-starring with Paris Hilton on The Simple Life, the new mom has appeared on shows such as 8 Simple Rules and American Dreams.

Richie also plans to launch her own jewelry line this fall, called House of Harlow 1960.

Sound off in the comments below!

Join the conversation