Season synopsis
Contains spoilers for this season and earlier seasons.
After Chuck uploads the upgraded Intersect, he spends six months training in Prague, hoping to qualify as a spy and build a future with Sarah. He repeatedly fails because he cannot call on his flashes when under pressure, and Beckman dismisses him from the program. Chuck had already refused Sarah’s plan to run away together; he returns to Burbank alone and depressed. Back at the Buy More, he resumes work with Morgan and slowly rejoins the spy team. Shaw takes charge of Chuck’s training, while Sarah and Casey keep watching for signs that the Intersect and the job are changing him. Missions bring Chuck closer to certification, but they do not resolve the conflict between his feelings for Sarah and his wish to be a spy.
Chuck and Sarah finally choose each other and leave the agency, but their honeymoon on a Swiss train is interrupted by a terrorist plot, drawing them and Casey back into action. By the season’s last two episodes, Ring agent Daniel Shaw returns with his own Intersect and helps frame the team. Ellie learns Chuck’s secret life, then watches Shaw kill their father Stephen and steal the governor Stephen built to stabilize Chuck’s glitching Intersect. Morgan, Ellie and Devon rescue Chuck, Sarah and Casey from a prison transfer. Chuck later outsmarts Shaw during a spy conference, helps expose the Ring Elders and defeats Shaw in a final fight at the Buy More, choosing to have him arrested rather than kill him. Shaw’s bombs destroy the store, and Ellie asks Chuck to leave espionage; he agrees. Stephen’s posthumous message then leads Chuck to a hidden lab beneath their childhood home, where he discovers their mother Mary is alive and was a spy.