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…

Sheldon and Amy await big news.

Sheldon and Amy are still down about their theory being disproven, but a VHS tape from Sheldon’s past inspires him not to give up. Bernadette turns into a pageant mom…

In the eleventh season opener, Amy gives Sheldon an answer to his proposal while Howard and Bernadette struggle with some unexpected news.

The gang is concerned when Sheldon’s former admirer, Dr. Ramona Nowitzki, resurfaces while Amy is away at Princeton.

Leonard isn’t thrilled when Penny considers taking a new job offered by her ex-boyfriend, Zack.

Howard and Bernadette have a hard time leaving Halley in day care when Bernadette returns to work. Also, Bert introduces the gang to his new girlfriend, Rebecca.

Sheldon pushes himself to the limit when he collaborates on projects with Leonard and Wolowitz as well as Amy on the same day. Also, Bernadette is nearing the end of…

Leonard, Penny and Raj adjust to their new living arrangement, and Sheldon takes an interest in Amy’s work.

When Raj moves out of his apartment, Leonard and Penny offer him Sheldon’s old room.

With Koothrappali cut off from his father’s fortune, he appoints Sheldon to help him get out of debt. Also, Penny considers joining Leonard at Comic-Con.

Sheldon and Amy have their first fight since moving in together, and Koothrappali is shocked at the realities of financial independence when he stops receiving support from his father.

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…

Sheldon beta-tests an MIT invention after hearing it can help him read people’s emotions. Also, Leonard can’t hide his feelings when Penny announces her brother is coming to town, and…

When Penny feels that Leonard is taking her for granted, she decides to go on a spa weekend with Amy. Also, Wolowitz and Koothrappali try to fix a squeaky floorboard…

Sheldon and Amy visit Leonard and Penny for the first time since the holidays and share details about their terrible trip to Texas.

Sheldon and Leonard try to divvy up their shared belongings, but can’t agree on anything. Also, Koothrappali and Stuart fight to be the most helpful during Bernadette’s final weeks of…

When Bert, a Caltech geologist, wins the MacArthur Genius fellowship, Sheldon is overcome with jealousy. Also, Wolowitz finds an old remote control Stephen Hawking action figure he invented.

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…

In order to continue living with Sheldon, Amy lies to him about repairs being made to her apartment and they host an “on location” episode of “Fun With Flags” in…

Penny is surprised to learn she has fans of her performance in “Serial Ape-ist” when she attends Van Nuys Comic Con with Leonard. Also, Amy hosts a Sheldon-style brunch at…

Leonard and Penny must separate a quarreling Sheldon and Amy when their cohabitation does not go as planned, and Sheldon threatens to break off their relationship when Amy refuses to…

When Amy’s apartment floods, she proposes a “cohabitation experiment” with Sheldon. Also, Howard and Bernadette are upset when Koothrappali learns the gender of the baby before they do.

Tensions rise when the boys struggle to complete their government project on time and Sheldon tries an energy drink to stay awake. Also, Penny and Amy go to a “party”…

Colonel Williams, an Air Force representative from the Department of Material Command sits down to talk with Wolowitz.

After Sheldon’s mother and Leonard’s father share an evening together, everyone deals with an awkward morning the next day. Also, Penny’s family arrives for the wedding ceremony, including her anxiety-ridden…

Chaos ensues when Leonard’s recently divorced parents, Alfred and Beverly, and Sheldon’s devoutly religious mother, Mary, come to town. Also, Wolowitz and Koothrappali think the government is out to get…

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

Sheldon spills a secret of Leonard’s when the two take a weekend cabin trip with Penny and Amy. Also, when Koothrappali goes overboard with pregnancy gifts, Wolowitz and Bernadette must…

Amy is shocked at a revelation from Sheldon after she buys him a new laptop. Also, Koothrappali sells out Leonard and Wolowitz after they lie to their wives in order…

Leonard, Sheldon, and Wolowitz run into problems when they file for a patent for their infinite persistence gyroscope. Also, Penny, Amy and Bernadette give Koothrappali dating advice when Emily reaches…

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

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…

Sheldon and Amy host a live Valentine’s Day episode of Fun with Flags, Leonard and Penny grapple with getting older, Howard and Bernadette find a surprise in their hot tub…

Meemaw meets Amy, but it isn’t all roses. Meemaw seems to have an axe to grind with her. Sheldon comes to Amy’s defense, but not before Meemaw lets a little…

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…

Sheldon has a revelation when he realizes why a song was stuck in his head. Also, Amy invites Dave over for dinner despite their previously awkward date, and Wolowitz and…

Sheldon and Amy try hanging out as friends when they spend Thanksgiving together at the aquarium. Also, Wolowitz reluctantly agrees to volunteer at the soup kitchen with Bernadette, Raj and…