When Sheldon hires a female grad student to assist him, a jealous Amy asks Penny to help her spy on them, only to make a shocking discovery. Life in the International Space Station is wearing on Howard.
The guys are stranded in the middle of nowhere when Leonard's car is stolen on the way to the Bakersfield Comic-Con. Back home, the girls try to figure out why the guys are so fascinated with comic books.
A date between Raj and Lucy takes both of them out of their comfort zones. After a trip to Las Vegas goes awry, the girls join in on a Dungeons & Dragons game, which causes Amy and Sheldon to reevaluate their relationship.