Bernadette and Wolowitz leave their kids for the first time; Penny and Leonard try to keep a secret; Sheldon and Amy stick together; and Koothrappali makes a new friend, as the gang travels together into an uncharted future.Watch Now:Amazon
After a successful experiment combining their genes, Sheldon will stop at nothing to convince Amy they should procreate. Also, Koothrappali is embarrassed to tell the gang what the new woman he’s dating does for a living.Watch Now:Amazon
Leonard and Penny deal with the idea of starting a relationship again and Raj finally finds a "woman" he can talk to without being drunk. Meanwhile, Sheldon decides to start a YouTube series entitled "Sheldon Cooper presents Fun with Flags" with the help of Amy.Watch Now:AmazoniTunes
When Leonard is considered for an exciting research opportunity, Sheldon becomes jealous and tries to scare him into backing out. Meanwhile, Raj's relationship with Lucy is strained when he tries to get her to meet his friends.Watch Now:Amazon
After Amy ruins one of Sheldon's favorite movies – Raiders of the Lost Ark – he gets defensive, seeking revenge. Meanwhile, Leonard discovers a way to get Penny to do anything; and Raj and Stuart create online dating profiles.Watch Now:Amazon
A fight between Sheldon and Leonard impacts Amy and Penny's living arrangements; while Howard is away, Raj helps Mrs. Wolowitz out.
As Leonard tries to help Penny with a disappointment, Penny asks him a bold question about their relationship; Meanwhile Raj and Stuart practice their skills at talking to women and Sheldon wants to learn how to be funny.Watch Now:Amazon
Trouble arises when Amy learns Sheldon has applied for a one-way mission to colonize Mars. Also, a trip to the pet store ends in a fight for Sheldon and Amy, Leonard surprises Penny with a very “adult” purchase, and Raj is caught snooping in Emily’s apartment.Watch Now:iTunes
Amy's desire to have an intimate night with Sheldon on her birthday is interrupted by Bernadette going into labor.
Penny gets help from Sheldon in order to understand what Leonard's work is, while Wolowitz develops a jealousy when Leonard starts hanging out with his new girlfriend.
Sheldon winds up in traffic court when he gets a ticket because of Penny.
Leonard can only bring one guest on a trip to see CERN's Large Hadron Collider (the world's largest and highest energy particle accelerator) in Switzerland on Valentine's Day.
Leonard and Wolowitz try to distract Sheldon when he slows the progress of their guidance system. Also, Penny and Amy take Bernadette out for the night, leaving Raj and Stuart to care for baby Halley.
It’s Thanksgiving. Sheldon and Amy go on a lunch date to the aquarium as friends. Meanwhile, Howard, Bernadette, Raj and Emily help out at a soup kitchen and Leonard and Penny make their first Thanksgiving dinner as a married couple.
The guys' annual trip to Comic Con is in doubt when Raj can't afford to go and an unexpected replacement is considered.
When the gang finds out about Bernadette's pregnancy, they celebrate by singing karaoke. Also, Bernadette is concerned when Wolowitz freaks out over her pregnancy announcement, and Wolowitz is convinced he must make more money to provide for a baby.
The guys try to help Penny out of an awkward work dilemma, when a smitten doctor shows up at her door after her flirtatious sales techniques work a little too well. Meanwhile, Amy and Bernadette argue over whether or not female scientists should play up their sexuality.Watch Now:iTunes