3 August 2010,

Stacy Keibler is joining the Nerd Herd. The wrestler-model-What About Brian actress has signed on to guest star on this season’s third episode of Chuck, sources confirm to me exclusively.
Keibler will succeed Olivia Munn and Isaiah Mustafa as undercover agent Greta, a new recurring character that will be played by a different actor every week.

“Greta can be a guy or a girl, which is brilliant,” Zachary Levi explained to me over the weekend at NBC’s press tour soiree. “The Buy More has now been taken over by the CIA and it’s a fully functioning operation by the government, so there are these constant agents that are in the store. First it was Olivia Munn, who looked hot in her little Nerd Hereder outfit, and [next was] Isaiah, who was a hoot to work with.”

Keibler’s episode—which also features the return of Nicole Richie and “Stone Cold” Steve Austin—is slated to air in October. - EW.com