At a BioScience conference, Chuck runs into Jill, his ex-girlfriend who broke up with him and later dated Bryce Larkin. He flashes on her boss, Guy Lafleur, who is suspected to be working on biochemical weapons. Chuck is ordered to reconnect with Jill in order to gain more information on Lafleur. Meanwhile, Emmett wants the staff to take CPR lessons including a test.

A new mission has Chuck and Sarah posing as a married couple and interacting with some odd neighbors. The Buy More crew help Big Mike out after his wife files for divorce.

After his last dream, Chuck asks Morgan to help him on a side mission. Their investigation becomes complicated when Stephen J. Bartowski returns and learns that Chuck downloaded the Intersect 2.0. Luckily, Chuck's father may be able to help his son.

Chuck tries to create a romantic getaway for Sarah while tracking down a nano-chip at a French vineyard. Lester asks Big Mike for love advice.

After a harrowing mission, Sarah returns to Chuck with a huge secret. Meanwhile, Ellie and Awesome are presented with a new opportunity that could change their lives.