Nicole Richie returned to Chuck as Heather on the show's 10/4/10 episode. She's seen here with Sarah.
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Chuck is talking to guest star Stone Cold Steve Austin in this shot from "Chuck Versus the Cubic Z." It's the fourth episode of season four.
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Hey, it's Stone Cold Steve Austin! The former wrestler guest stars on the Chuck episode "Chuck Versus the Cubic Z."
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Chuck Season 4 Episode 3 Quotes

Sarah: We don't have the authority to interrogate Chandler.
Chuck: Well we don't have the authority to use the supply closet for what it is we use it for, but we do it anyway. Don't we?

You're acting awful bitchie Burton, or whatever it is you go by.

Heather