Penny and Leonard deal with Leonard's confession on the way down the aisle while Sheldon struggles to understand Amy's decision to take a step back from their relationship.
In the Season 8 finale, Leonard and Penny are pressured to set a wedding date by Sheldon, whose relationship with Amy has taken an interesting turn.
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 help from his friends.moreless
When Leonard is set to give the commencement address at his former high school, a canceled flight threatens to stop him giving the speech. Meanwhile, Howard's engineering skills are tested when he and Sheldon try fix Raj's toy helicopter, while Raj plays his parents against each other after his father cuts him off financially.moreless
When Raj is asked to submit a proposal to NASA, the guys end up in a fight. Penny wonders what to do when she asked to audition for a movie role.
When Sheldon and Amy build a blanket fort, they come to major crossroads in their relationship. Also, Wolowitz meets the half-brother he never knew he had, and when Penny is invited to appear on Wil Wheaton's podcast, she and Leonard have a huge, on-air argument.moreless
A speaking engagement at UC Berkeley puts Leonard and Sheldon in a galaxy not too far, far away from their idol George Lucas' Skywalker Ranch, and they consider dropping by. Meanwhile, Howard and Bernadette argue over what to do with his Doctor Who TARDIS, so Raj and Amy try to settle things with a game of table tennis.moreless
An electrical short thaws the last meal that was cooked by Mrs. Wolowitz, and the gang ponders what to do with it, while Sheldon and Leonard's work is featured in a magazine, but only one receives credit.moreless
There's trouble in paradise when Amy discovers Sheldon signed up for a one-way mission to colonize Mars, and the two get into a dogfight at a pet store. Meanwhile, Leonard makes a very "adult" purchase for Penny; and Emily catches Raj snooping in her apartment.moreless
As a joke, Sheldon and Penny try an experiment designed to make participants fall in love. Also, Leonard, Amy, Raj and Emily spend the evening trying to escape a room with a "zombie." And, after returning from Mrs. Wolowitz' funeral, Bernadette and Howard run into trouble at the airport.moreless
Amid the excitement of Stuart reopening his comic-book store, Howard gets some unsettling news; and after teaching Sheldon how to "let it go," Penny doesn't practice what she preaches when she learns something maddening about Amy. Meanwhile, Raj and Leonard run into a restaurant customer who looks a lot like actor Nathan Fillion.moreless
An online troll rips Leonard and Sheldon's published physics paper, so the guys rally to defend the two and expose the bully, while a girls night out leads to Penny, Amy and Bernadette dishing about embarrassing past events.moreless
Sheldon becomes concerned that his cushy lifestyle is impacting his professional progress and keeping him from achieving scientific renown, so he asks the gang to make life more difficult for him. Meanwhile, Howard invents an unflattering game about Raj.moreless
While Raj eagerly awaits data from a space probe in which he was involved, Howard keeps distracting him. Later, dress shopping with Penny and Amy doesn't exactly prove to be a good fit for Leonard and Sheldon.moreless
On Christmas Eve, Amy plans a traditional Victorian dinner, while Raj, Leonard and Howard scramble to remove a pigeon that flew into the clean room at the university. To prove a point to Amy, a Scrooge-like Sheldon buys her the worst possible gift.moreless
Leonard, Raj and Howard clean out the office of the deceased Professor Roger Abbot and find a bottle of champagne meant to be opened when he made his first great scientific discovery. Meanwhile, Sheldon prepares his final episode of "Fun with Flags". Bernadette discovers that people are afraid of her.moreless
Leonard needs surgery for a deviated septum, and Sheldon gets his nose out of joint because he feels an operation is too dangerous and that his roommate may not make it out alive. Meanwhile, a distraught Raj learns his parents have divorced on the eve of their 40th anniversary.moreless
Amy and Bernadette organize a prom to be held atop the guys' apartment complex, but Sheldon is leery of all the prom pomp, circumstance and romancing that goes with it.
Penny's flirtatious sales pitch is misunderstood by a doctor-client, while Bernadette and Amy debate whether female scientists ought to play the sexuality card.
Sheldon and Raj undertake an underground research expedition that turns into a test of how long before they get under each other's skin. Meanwhile, Leonard and Penny argue about money, and go to Wolowitz and Bernadette for advice.moreless
While Amy, Penny and Bernadette have a girls weekend in Vegas, Penny ends up having to study at the last minute, while Amy and Bernadette go out and get drunk. Back at home, with the girls gone, the four guys want to invent something new, but keep focusing on other things.moreless
Raj's brings his new girlfriend over to meet the gang, but she seems standoffish with Penny, who tries to figure out why. Meanwhile, the guys put their heads together to try to re-open Stuart's comic book store.moreless
A nervous Wolowitz is thrown for a loop when NASA asks him to toss out the first pitch at a Los Angeles Angels baseball game. Meanwhile, Sheldon brags that he and Amy are a better couple than Leonard and Penny, so they set out to prove he's way off base.moreless
In the Season 8 premiere, Amy and Leonard take a surprise road trip to Arizona to retrieve Sheldon, while Penny goes on a job interview at Bernadette's company, and Howard has problems wrapping his head around Stuart's relationship with Mrs. Wolowitz.moreless
Sheldon is ordered to teach a class, and the gang is surprised when Howard signs up to take it; and tensions between Penny and Bernadette afford Amy an opportunity to play one against the other.moreless
In the Season 7 finale, Sheldon gets caught up in all the life-altering changes going on around him and considers a monumental move.