The BEST episodes of The Big Bang Theory season 9

Every episode of The Big Bang Theory season 9, ranked from best to worst by thousands of votes from fans of the show. The best episodes of The Big Bang Theory season 9!

A woman who moves into an apartment across the hall from two brilliant but socially awkward physicists shows them how little they know about life outside of the laboratory.

Last Updated: 12/10/2024Network: CBSStatus: Ended
The Opening Night Excitation
star
8.21
7423 votes

#1 - The Opening Night Excitation

Season 9 - Episode 11 - Aired 12/17/2015

As the guys prepare to go to the premiere of the new Star Wars movie, Sheldon plans a special event for Amy's birthday.

Directors: Mark Cendrowski
Watch Now:AmazonApple TV
The Earworm Reverberation
star
7.87
7119 votes

#2 - The Earworm Reverberation

Season 9 - Episode 10 - Aired 12/10/2015

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 Koothrappali become obsessed with a fan of their band, "Footprints on the Moon."

Directors: Mark Cendrowski
Watch Now:AmazonApple TV
The Convergence Convergence
star
7.81
8027 votes

#3 - The Convergence Convergence

Season 9 - Episode 24 - Aired 5/12/2016

Leonard and Penny get remarried in front of their friends, Leonard's parents, Beverly and Alfred and Sheldon's mother, Mary, who finds something in common with Alfred. Howard gets an unknown email from the Air Force about his invention.

Directors: Mark Cendrowski
Watch Now:AmazonApple TV
The Positive Negative Reaction
star
7.72
7301 votes

#4 - The Positive Negative Reaction

Season 9 - Episode 16 - Aired 2/18/2016

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.

Directors: Mark Cendrowski
Watch Now:Apple TV
The Platonic Permutation
star
7.72
6902 votes

#5 - The Platonic Permutation

Season 9 - Episode 9 - Aired 11/19/2015

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.

Directors: Mark Cendrowski
Watch Now:Apple TV
The Mystery Date Observation
star
7.70
6881 votes

#6 - The Mystery Date Observation

Season 9 - Episode 8 - Aired 11/12/2015

Amy has a formal date which Leonard, Penny and Bernadette secretly spy on. Sheldon has Howard and Raj help him find a new girlfriend since they found Amy for him.

Directors: Mark Cendrowski
Watch Now:Apple TV
The Bachelor Party Corrosion
star
7.69
7330 votes

#7 - The Bachelor Party Corrosion

Season 9 - Episode 3 - Aired 10/5/2015

The guys’ science skills are put to the test when they get a flat tire during Leonard’s bachelor party weekend in Mexico. Also, the girls force Penny to finally tell her family that she eloped with Leonard.

Directors: Mark Cendrowski
Watch Now:Apple TV
The Application Deterioration
star
7.69
7037 votes

#8 - The Application Deterioration

Season 9 - Episode 18 - Aired 3/10/2016

Sheldon works up a contract to split their portion of their guidance system invention royalties, but Bernadette does not like how it's done. Raj must again decide between Emily and Claire when they both contact him.

Directors: Mark Cendrowski
Watch Now:Apple TV
The Spock Resonance
star
7.67
6947 votes

#9 - The Spock Resonance

Season 9 - Episode 7 - Aired 11/5/2015

Adam Nimoy, friend of Wil Wheaton and son of Leonard Nimoy, interviews Sheldon for a "Star Trek" documentary, but Sheldon goes off topic and has trouble suppressing his emotions about his recent break-up from Amy. Bernadette wants to start renovating the house and the issue of starting a family with Howard is brought up.

Directors: Nikki Lorre
Watch Now:Apple TV
The Valentino Submergence
star
7.66
7036 votes

#10 - The Valentino Submergence

Season 9 - Episode 15 - Aired 2/11/2016

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 and Raj is torn between Emily and the cute girl he met at the Comic Bookstore.

Directors: Mark Cendrowski
Watch Now:Apple TV
The Empathy Optimization
star
7.66
7009 votes

#11 - The Empathy Optimization

Season 9 - Episode 13 - Aired 1/14/2016

The gang decides to head to Vegas for the week on a party bus. Sheldon learns about the importance of empathy and saying sorry.

Directors: Mark Cendrowski
Watch Now:Apple TV
The Meemaw Materialization
star
7.65
7082 votes

#12 - The Meemaw Materialization

Season 9 - Episode 14 - Aired 2/4/2016

Sheldon is thrilled when his Meemaw comes to visit, but his excitement quickly fades when she butts heads with Amy. Also, Raj meets a new girl at the comic book store who makes him question his relationship with Emily.

Directors: Mark Cendrowski
Watch Now:Apple TV
The Fermentation Bifurcation
star
7.65
7926 votes

#13 - The Fermentation Bifurcation

Season 9 - Episode 22 - Aired 4/28/2016

Sheldon and Bernadette spend a night together while the rest of the gang goes to a wine tasting party, but things get uncomfortable for Raj when Zack also attends and takes an interest in Claire.

Directors: Nikki Lorre
Watch Now:Apple TV
The Big Bear Precipitation
star
7.62
7936 votes

#14 - The Big Bear Precipitation

Season 9 - Episode 20 - Aired 4/7/2016

Secrets are revealed when Amy and Sheldon join Penny and Leonard on a weekend cabin trip. Raj is more excited about Howard's and Bernadette's impending parenthood than they are.

Directors: Mark Cendrowski
Watch Now:Apple TV
The Solder Excursion Diversion
star
7.62
7672 votes

#15 - The Solder Excursion Diversion

Season 9 - Episode 19 - Aired 3/31/2016

Amy is shocked at a revelation from Sheldon after she buys him a new laptop. Koothrappali sells out Leonard and Wolowitz after they lie to their wives in order to attend an early screening of a movie.

Directors: Mark Cendrowski
Watch Now:Apple TV
The Viewing Party Combustion
star
7.62
7949 votes

#16 - The Viewing Party Combustion

Season 9 - Episode 21 - Aired 4/21/2016

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

Directors: Mark Cendrowski
Watch Now:Apple TV
The Celebration Experimentation
star
7.62
7096 votes

#17 - The Celebration Experimentation

Season 9 - Episode 17 - Aired 2/25/2016

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

Directors: Mark Cendrowski
Watch Now:Apple TV
The Separation Oscillation
star
7.62
7229 votes

#18 - The Separation Oscillation

Season 9 - Episode 2 - Aired 9/28/2015

Leonard confronts the woman he kissed on the North Sea in an attempt to set Penny’s mind at ease. Also, Sheldon films a special episode of “Fun with Flags” after his breakup with Amy, and Bernadette feels guilty about withholding a secret from Penny.

Directors: Mark Cendrowski
Watch Now:Apple TV
The Line Substitution Solution
star
7.61
7828 votes

#19 - The Line Substitution Solution

Season 9 - Episode 23 - Aired 5/5/2016

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 connection with her.

Directors: Anthony Rich
Watch Now:Apple TV
The Perspiration Implementation
star
7.59
6888 votes

#20 - The Perspiration Implementation

Season 9 - Episode 5 - Aired 10/19/2015

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 customers at the Comic Book Store, Penny, Amy and Bernadette come by to help him out.

Directors: Mark Cendrowski
Watch Now:Apple TV
The Sales Call Sublimation
star
7.59
7041 votes

#21 - The Sales Call Sublimation

Season 9 - Episode 12 - Aired 1/7/2016

Leonard visits a psychiatrist so Penny can make a sales call. Stuart moves out of the Wolowitz house. Sheldon works with Raj looking for extra-solar planets.

Directors: Mark Cendrowski
Watch Now:Apple TV
The 2003 Approximation
star
7.56
6924 votes

#22 - The 2003 Approximation

Season 9 - Episode 4 - Aired 10/12/2015

Leonard and Penny finally move in together leaving Sheldon very upset with this big change in his life and wishing he could go back to a time when he had no emotions in 2003 before he met Leonard. Raj, Howard and Stuart attempt to form a band.

Directors: Mark Cendrowski
Watch Now:Apple TV
The Helium Insufficiency
star
7.52
6674 votes

#23 - The Helium Insufficiency

Season 9 - Episode 6 - Aired 10/26/2015

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 phone to try and find her a new man.

Directors: Mark Cendrowski
Watch Now:Apple TV
The Matrimonial Momentum
star
7.49
7640 votes

#24 - The Matrimonial Momentum

Season 9 - Episode 1 - Aired 9/21/2015

Sheldon is confronted by a mystery of the universe he cannot unravel: when Amy presses pause on their relationship. Meanwhile, in Las Vegas, Penny struggles with Leonard's confession that he kissed another girl.

Directors: Mark Cendrowski
Watch Now:Apple TV