US TV
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Entertainment Weekly reports that the actress will play undercover CIA agent Greta in the eighth episode.
Each new episode of Chuck will feature a different star as Greta. Olivia Munn played the role in the season premiere, while Stacy Keibler and Isaiah Mustafa will feature in future instalments.
Glau previously starred in Terminator: The Sarah Connor Chronicles and will next be seen in NBC's upcoming superhero drama The Cape.
The fourth season of Chuck continues on Mondays at 8/7c on NBC. Glau's episode is expected to air in November.
More: Summer Glau, US TV
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