US Air Date: 05/11/2007

Writer: Anne Corfell Saunders

Director: Patrick Norris

“Wow, sarcasm. What a surprise” Chuck compliments the usually straight-talking Casey on his use of the lowest form of humour

At Stanford, Professor Fleming spies a big man entering the lecture hall as his class is leaving. He flees to his office where he makes a call, using code name Black Castle. He says he's made a mistake by copying intel onto a disk – now they're after it. He disappears down a trap door in the closet as the big guy busts through the door.

Chuck is surprised to learn that the guy who expelled him from Stanford, Professor Fleming, is CIA and has gone missing. Beckman asks for Chuck's help; Chuck tells her to find someone else, but Casey demands Chuck help bring him in. Chuck flashes back to the moment Fleming accused him of stealing test answers from his office; Chuck denied it, but Fleming sided with his informant, Bryce.

They find Fleming, but a sniper, Magnus, takes him out. Fleming tries to give Chuck a list of numbers, but Magnus retrieves it. Chuck realises that the numbers on Fleming's note point to a library book – Fleming must have stashed his disk there.

Chuck finds the hidden disk but a librarian interrupts, claiming Chuck owes over $300 in late fees. Magnus appears and they flee to a lecture hall, where they check the contents of the disk. It contains ten years of files on students recruited into the CIA by Fleming. Chuck calls the students and uses a code word to get them to come to the campus and defeat Magnus. At home, Chuck checks his file and realises that Bryce framed him to save him from being recruited, and couldn't tell because he was already in the CIA.