Sheldon hires Stuart to spend the day with Amy when he’d rather go to a movie screening. Also, Leonard’s mother, Beverly, comes to town and Penny struggles to make a…

Everyone must choose sides when a small argument between Leonard and Sheldon erupts into a heated fight during a group get-together.

After more than nine years together, the gang finally celebrates Sheldon’s birthday, surprising him with a special guest.

After having to deal with a sick Sheldon, Leonard, Penny and the gang try to treat themselves to a Sheldon-free weekend.

Penny gets more than she bargained for when Leonard agrees to meet with a psychiatrist on her behalf. Also, Sheldon and Koothrappali collaborate on an astronomical discovery, and Wolowitz and…

After more than five years of dating, Sheldon and Amy spend their first night together. Also, Leonard, Wolowitz, and Koothrappali must decide who will take their extra Star Wars movie…

In the midst of a nation-wide helium shortage, Sheldon and Leonard take desperate measures to get the supplies they need. Also, Penny and Bernadette download a dating app on Amy’s…

The guys take a fencing lesson from Barry Kripke and Sheldon finds himself in an awkward position when Kripke expresses interest in Amy. Also, when Stuart struggles to get female…

Sheldon learns of an impending change in his living arrangements and decides to revert back to 2003, a simpler time before he met Leonard and Penny. Also, Howard and Raj…

After driving to Vegas to get married, Penny struggles with Leonard’s confession that he kissed another girl. Also, Sheldon doesn’t know how to act after Amy pushes pause on their…

Sheldon pushes Leonard and Penny to choose a date for their wedding and deals with dramatic changes in his own relationship with Amy.

Personalities collide when Sheldon and Leonard’s mothers finally meet. Meanwhile, Howard finally decides to “man up” and do his fair share of the housework – but not without a little…

Friction ensues when a magazine fails to mention Leonard in an article about the paper he co-wrote with Sheldon. Also, a blackout at Mrs. Wolowitz’s home leads to a final…

Wolowitz receives some shocking news as everyone prepares for the reopening of Stuart’s comic book store. Penny teaches Sheldon how to “let it go,” but can’t follow her own advice…

When the gang recreates a high-school prom night on the roof of the guys’; apartment building, Sheldon feels pressure to participate in all the typical romantic traditions.

Raj’s honesty comes back to haunt him when his new girlfriend is unfriendly to Penny. The guys think about becoming part owners in Stuart’s store.

Leonard and Amy make an unexpected trip to Arizona to fetch Sheldon; Penny interviews for a job at Bernadette’s company; Stuart’s relationship with Mrs. Wolowitz disturbs Howard.

After the guys throw Howard a bachelor party, Bernadette reconsiders marrying him after learning about his sexual history.

Sheldon must choose between joining Amy at her aunt’s birthday party or playing videogames all weekend with the guys.

Sheldon’s selfish demands force Leonard to reconsider their friendship. Meanwhile, Wolowitz tries to pick his astronaut nickname.

When Stuart asks Amy out on a date, Sheldon must confront his feelings and consider where his relationship with Amy is going.

A cute comic book artist puts Leonard and Priya’s relationship to the test, while Sheldon tries to scare the guys for Halloween.

Sheldon and Leonard get invited to a party at Wil Wheaton’s house, and Howard gets an out-of-this-world opportunity.

The Wolowitzes’ life gets complicated when Stuart starts bringing his new girlfriend home. Penny and Leonard talk about starting a family. Raj explores an arranged marriage.

Sheldon and Amy drive themselves crazy trying to figure out what ‘perfect gift’ Leonard and Penny gave them for their wedding. Raj decides he wants to settle down and asks…

After a bad date, Koothrappali decides to never leave his apartment; Penny’s acting skills impress Sheldon.

The guys search for a perfect Valentine’s Day gift for their significant others; Stuart and Raj host a “lonely people” party at the comic book store.

As the guys don costumes and go on a road trip to a comic book convention, the ladies decide to stay home and try to interpret a comic book.

During a game, Sheldon revisits Christmas memories; Amy, Penny and Bernadette look for a date for Koothrappali.

The gang celebrates Halloween at Stuart’s comic book store. Meanwhile, Leonard seduces Penny with science.

When Wolowitz returns from space, he doesn’t get the hero’s welcome he expected. Meanwhile, Game Night turns into a battle of the sexes.

When Sheldon learns that Penny is thinking about breaking up with Leonard, he tries to intervene. Meanwhile, in space, the other astronauts pick on Howard.

With his friends on dates, Raj must face his loneliness. Also, Wolowitz is caught in an argument between Bernadette and his mom, even while he’s in space

Sheldon get upset about his career, the destruction of the comic book store and Leonard and Penny’s future living arrangements. Howard and Bernadette can’t keep hold of a carer for…

When Sheldon visits his Mom in Houston, he is forced to confront a new reality. Meanwhile, Raj’s ‘Murder Mystery’ party starts some fights within the gang.

Sheldon tries to relax after he is forced to take a vacation. Meanwhile, Leonard struggles to be supportive of Penny after she quits her job, and Bernadette seeks Stuart’s help…

When Penny’s big acting break on NCIS is a bust, Leonard struggles to help her, which results in Penny asking Leonard a bold relationship question. Meanwhile, Sheldon tries to learn…

While Sheldon is in Texas, the rest of the gang realizes how much he has changed their lives as they decorate the apartment Christmas tree.

Beverly Hofstadter writes a psychology book about Leonard which Penny buys and reads. Sheldon wants to ruin something for Amy after she ruins an Indiana Jones movie for him. Raj…

When the entire gang competes in a scavenger hunt designed by Raj, it brings out the best – and worst – in everyone.