The Big Bang Theory of Everything
In the hour-long series finale, Sheldon and Amy await big news, Howard and Bernadette leave their kids for the first time, Leonard and Penny try to keep a secret, and Raj makes a new friend
Leonard is surprised when his mother Beverly visits and is kind to him, until he finds out the real reason she's there. Denise and Stuart overstay their welcome at Howard and Bernadette's house.
When Barry Kripke finds proof that Dr Pemberton plagiarised his thesis in college, Sheldon and Amy aren't sure whether they should turn their rival in or not. Howard makes a happy discovery.
Raj is worried that people won't take him seriously in his own field after publishing a paper that suggests he may have discovered alien life. Penny encourages Leonard to stand up for himself.
Amy has a meltdown when she feels the pressure of what it would mean for women everywhere if she were to win a Nobel Prize. Howard buys a scooter that looks like the one he had years ago.
When their academic competitors charm America on a publicity tour, Sheldon and Amy try to bring some Nobel laureates to their side. Halley's fear of the dark affects Howard, Bernadette and Stuart.
Penny and Bernadette go to San Diego for a pharmaceutical sales convention, leaving Howard in charge of the children. Then Sheldon finds a book containing science experiments to carry out with kids...
When the gang find out that Wil Wheaton is hosting a celebrity game of Dungeons & Dragons at his home, deception and betrayal take hold as they compete to occupy the one open seat at the event
Penny attempts to sabotage Leonard's efforts to help her ex-boyfriend Zack and his wife Marissa have a family of their own. Raj's cancelled bachelor party turns into a couples' trip.
Sheldon is thrilled to help Howard and Bernadette navigate some bureaucratic paperwork, until he discovers they are breaking the law. Leonard is excluded from his friends' scientific project.
Sheldon and Amy are thrilled when their super-asymmetry theory is proved correct by two physicists from Chicago. Bernadette enjoys some big success at work and plans for Penny to become a part of it.
Penny's former boyfriend Zack and his wife want to have a baby, but when they encounter fertility problems, they ask Leonard for his help. Raj tries to patch things up with his estranged fiancée Anu.
Sheldon is jealous when Amy gets media attention, Raj spots Anu talking to her ex-boyfriend, Stuart is intimidated by the idea of moving in with Denise, and Penny and Leonard organise a paintball game
Sheldon and Amy are still upset about their theory being disproven, but a VHS tape from Sheldon's past inspires him not to give up. Howard prepares his magic act for a very important audition.
Sheldon and Amy are devastated to learn that super-asymmetry has already been discovered and disproven. Bernadette asks Stuart's girlfriend Denise to teach her how to beat Howard at a video game.
Sheldon tries to befriend Amy's father, but when Howard lures Mr Fowler away with his magic tricks Sheldon has no choice but to bond with Mrs Fowler. Meanwhile, Raj and Anu attempt to get physical.
Leonard is caught between a rock and a hard place when he is made responsible for distributing extra grant money. Bernadette turns the back garden playhouse into a hideaway to escape from her family.
When Howard dresses up as Sheldon for Halloween, Sheldon gets his own back at Leonard and Penny's Halloween party. Meanwhile, Leonard is shocked that Penny doesn't remember their first kiss.
When Amy doesn't have time to help Sheldon with his work, he goes to great lengths to ensure that she's available. Raj isn't keen when Howard is invited to join him to host a show at the planetarium.
When Sheldon won't tell anyone why he's never mentioned Tam, his childhood best friend, Leonard tries to find out. Penny and Bernadette invite Raj's fiancée Anu out for dinner to get to know her.
Howard and Bernadette's life becomes complicated when Stuart starts bringing his new girlfriend home. Penny and Leonard talk about starting a family. Raj explores the possibility of arranged marriage.
Sheldon and Amy drive themselves to distraction trying to figure out what the 'perfect gift' is that Leonard and Penny got them for their wedding. Raj decides he wants to settle down.
Sheldon and Amy's honeymoon runs aground in New York. Penny and Leonard discover they are uncomfortably similar to Amy's parents. Raj starts a social media war with astrophysicist Neil deGrasse Tyson.