She may be a new mom, but she still knows how to get dirty.

On next week’s Chuck, Nicole Richie shows us that she’s come a long way since her bleach pouring days on The Simple Life. In the episode, Nicole plays Heather Chandler (Heathers, anyone?) a former high school rival of Sarah’s.

Unfortunately for Walker, the CIA agent is forced to attend a conveniently-timed high school reunion to deal with a person who just happens to be married to Richie. She is also forced to deal with the awkward memories she tried so hard to leave behind.

You can see several of the upcoming scenes - including one where Paris Hilton’s former/current BFF kicks ass - after the jump.

You can see the girl fight on Chuck this Monday, October 20 at 8:00.