email from Bryce. The NSA's Major John Casey (Adam Baldwin) and CIA Officer Sarah Walker (Yvonne Strahovski) are dispatched to investigate. Chuck is recruited to use the knowledge he now possesses to help thwart assassins and international terrorists, upending his previously mundane life. The Intersect causes Chuck to receive involuntary "flashes" of information from the database, activated by triggers such as faces, voices, objects, and keywords. In order to protect his family and friends, Chuck must keep his second occupation a secret. Casey and Walker are assigned to watch over Chuck. They are forced to establish an uneasy alliance and cover-identities. Walker poses as Chuck's girlfriend and takes a job at a fast food restaurant near the Buy More. Casey reluctantly becomes part of the Buy More sales team. The main antagonists driving the plot are a series of rogue spy cabals, first internal to the United States intelligence community and then global in scope. A core part of the threat is the danger of the Intersect being either captured, making Chuck as much a liability as an asset to the government, or replicated, making Chuck obsolete or outmatched by less scrupulous spies. Chuck, Sarah, and Casey all face professional conflicts as they grow to respect each other. A genuine romantic interest develops between Chuck and Sarah. Chuck's desire to maintain his close relationships and eventually return to a normal life is challenged by the dangers and growing responsibilities of his secret life, so that he gradually becomes a more competent, confident, and willing spy. In later seasons, upgrades to the Intersect would include skills in espionage as well as information (the reason the Intersect was originally conceived), giving Chuck temporary knowledge of hand-to-hand combat and other skills such as playing the guitar, using a zipline, foreign languages, dancing, and firearms training. In the course of events, Chuck unravels mysteries from his life before the series, often dealing with the Intersect, such as why his parents left, why Bryce got him kicked out of Stanford, and why he's unusually suited for the Intersect. Meanwhile, Casey and Sarah confront unresolved issues from their lives before the series, including their families, Sarah's history with Bryce, and the spies they previously worked with. And as Chuck grows more comfortable with his own role, those closest to him are gradually drawn into his spy life. Cast and characters Main cast Recurring cast Tony Todd