The BEST episodes of The Big Bang Theory season 5

Every episode of The Big Bang Theory season 5, ranked from best to worst by thousands of votes from fans of the show. The best episodes of The Big Bang Theory season 5!

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 Good Guy Fluctuation
star
8.05
13204 votes

#1 - The Good Guy Fluctuation

Season 5 - Episode 7 - Aired 10/27/2011

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

Directors: Mark Cendrowski
Watch Now:AmazonApple TV
The Countdown Reflection
star
7.99
11515 votes

#2 - The Countdown Reflection

Season 5 - Episode 24 - Aired 5/10/2012

As Howard's mission to space approaches, Howard and Bernadette decide to get married before his launch, causing the gang to scurry into overdrive in an effort to stage the wedding.

Directors: Mark Cendrowski
Watch Now:AmazonApple TV
The Hawking Excitation
star
7.89
11642 votes

#3 - The Hawking Excitation

Season 5 - Episode 21 - Aired 4/5/2012

When Wolowitz gets to work with Stephen Hawking, Sheldon is willing to do anything to meet his hero.

Directors: Mark Cendrowski
Watch Now:AmazonApple TV
The Beta Test Initiation
star
7.89
12128 votes

#4 - The Beta Test Initiation

Season 5 - Episode 14 - Aired 1/26/2012

Leonard and Penny deal with the idea of starting a relationship again and Raj finally finds a "woman" he can talk to without being drunk. Meanwhile, Sheldon decides to start a YouTube series entitled "Sheldon Cooper presents Fun with Flags" with the help of Amy.

Directors: Mark Cendrowski
Watch Now:AmazonApple TV
The Launch Acceleration
star
7.89
11179 votes

#5 - The Launch Acceleration

Season 5 - Episode 23 - Aired 5/3/2012

When NASA moves up Howard's mission, he must face his fears and Bernadette's dad, thus putting the wedding plans in jeopardy. Meanwhile, Leonard says something surprising to Penny in the bedroom.

Directors: Mark Cendrowski
Watch Now:AmazonApple TV
The Werewolf Transformation
star
7.88
11642 votes

#6 - The Werewolf Transformation

Season 5 - Episode 18 - Aired 2/23/2012

Sheldon becomes agitated when his regular barber is out sick. Astronaut training causes Howard to reconsider wanting to go into space. Penny beats Leonard in chess, the first time she plays.

Directors: Mark Cendrowski
Watch Now:AmazonApple TV
The Weekend Vortex
star
7.80
11868 votes

#7 - The Weekend Vortex

Season 5 - Episode 19 - Aired 3/8/2012

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

Directors: Mark Cendrowski
Watch Now:AmazonApple TV
The Recombination Hypothesis
star
7.79
12250 votes

#8 - The Recombination Hypothesis

Season 5 - Episode 13 - Aired 1/19/2012

Leonard, who broke up with Priya, asks Penny out to a spur-of the-moment romantic dinner for two, and the duo contemplates resuming their relationship.

Directors: Mark Cendrowski
Watch Now:AmazonApple TV
The Stag Convergence
star
7.79
11112 votes

#9 - The Stag Convergence

Season 5 - Episode 22 - Aired 4/26/2012

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

Directors: Peter Chakos
Watch Now:AmazonApple TV
The Russian Rocket Reaction
star
7.78
12604 votes

#10 - The Russian Rocket Reaction

Season 5 - Episode 5 - Aired 10/13/2011

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

Directors: Mark Cendrowski
Watch Now:AmazonApple TV
The Flaming Spittoon Acquisition
star
7.77
12511 votes

#11 - The Flaming Spittoon Acquisition

Season 5 - Episode 10 - Aired 11/17/2011

Sheldon considers taking his relationship with Amy to the next level when Stuart from the comic book store asks her out on a date.

Directors: Mark Cendrowski
Watch Now:AmazonApple TV
The Infestation Hypothesis
star
7.76
13277 votes

#12 - The Infestation Hypothesis

Season 5 - Episode 2 - Aired 9/22/2011

A fight between Sheldon and Penny leaves Amy caught in the middle. Meanwhile, Leonard tries to spice up his long-distance relationship with Priya.

Directors: Mark Cendrowski
Watch Now:Apple TV
The Wiggly Finger Catalyst
star
7.76
13249 votes

#13 - The Wiggly Finger Catalyst

Season 5 - Episode 4 - Aired 10/6/2011

Penny plays Matchmaker for Raj, which results in him finding a girl he is comfortable talking to, but the gang suspects that she may be taking advantage of Raj.

Directors: Mark Cendrowski
Watch Now:Apple TV
The Pulled Groin Extrapolation
star
7.75
13045 votes

#14 - The Pulled Groin Extrapolation

Season 5 - Episode 3 - Aired 9/29/2011

Leonard and Amy get to know each other better when Amy invites Leonard to a wedding. Meanwhile, Howard and Bernadette spend the weekend with Mrs. Wolowitz.

Directors: Mark Cendrowski
Watch Now:Apple TV
The Transporter Malfunction
star
7.72
11532 votes

#15 - The Transporter Malfunction

Season 5 - Episode 20 - Aired 3/29/2012

Penny buys Leonard and Sheldon “Star Trek” collectibles as a thank-you, leading Sheldon to be haunted by Mr. Spock. Meanwhile, Raj decides he has met the “Future Mrs. Koothrappali” after his parents set him up on a date.

Directors: Mark Cendrowski
Watch Now:Apple TV
The Rothman Disintegration
star
7.70
11954 votes

#16 - The Rothman Disintegration

Season 5 - Episode 17 - Aired 2/16/2012

Sheldon and his rival Barry Kripke fight it out over the availability of a new office. Penny gets a gift from Amy that really tests their friendship and it doesn't end well.

Directors: Mark Cendrowski
Watch Now:Apple TV
The Ornithophobia Diffusion
star
7.70
12501 votes

#17 - The Ornithophobia Diffusion

Season 5 - Episode 9 - Aired 11/10/2011

Leonard and Penny try hanging out as friends on a 'non-date,' but end up purposely ruining each others chances with perspective dates. Meanwhile, Sheldon enlists the help of Bernadette and Amy to overcome his fear of birds.

Directors: Mark Cendrowski
Watch Now:Apple TV
The Friendship Contraction
star
7.70
12151 votes

#18 - The Friendship Contraction

Season 5 - Episode 15 - Aired 2/2/2012

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

Directors: Mark Cendrowski
Watch Now:Apple TV
The Skank Reflex Analysis
star
7.69
13921 votes

#19 - The Skank Reflex Analysis

Season 5 - Episode 1 - Aired 9/22/2011

Penny is worried with how damaged her friendship with the guys will be in the aftermath of her sleeping with Raj, while Sheldon becomes the leader of the paintball team.

Directors: Mark Cendrowski
Watch Now:Apple TV
The Shiny Trinket Maneuver
star
7.69
12328 votes

#20 - The Shiny Trinket Maneuver

Season 5 - Episode 12 - Aired 1/12/2012

Sheldon gets in trouble with Amy when he isn't impressed by her recent accomplishment, and Howard must come to grips with Bernadette's dislike of children.

Directors: Mark Cendrowski
Watch Now:Apple TV
The Vacation Solution
star
7.68
11628 votes

#21 - The Vacation Solution

Season 5 - Episode 16 - Aired 2/9/2012

When Sheldon is forced to take his vacation, he goes to work with Amy in her neurobiology lab. Also, Bernadette wants Howard to sign a pre-nup.

Directors: Mark Cendrowski
Watch Now:Apple TV
The Rhinitis Revelation
star
7.67
12604 votes

#22 - The Rhinitis Revelation

Season 5 - Episode 6 - Aired 10/20/2011

Sheldon's mother, Mary Cooper, comes to visit, but Sheldon is annoyed that she also spends time with the rest of the gang, instead of catering to his every demand.

Directors: Howard Murray
Watch Now:Apple TV
The Isolation Permutation
star
7.59
12264 votes

#23 - The Isolation Permutation

Season 5 - Episode 8 - Aired 11/3/2011

Amy becomes heartbroken when she discovers that Penny and Bernadette went wedding dress shopping without her and turns to a reluctant Sheldon for comfort.

Directors: Mark Cendrowski
Watch Now:Apple TV
The Speckerman Recurrence
star
7.47
12163 votes

#24 - The Speckerman Recurrence

Season 5 - Episode 11 - Aired 12/8/2011

When Leonard's former high school tormentor resurfaces, Leonard must confront him. Meanwhile, Penny realizes she did her fair share of tormenting in the past.

Directors: Anthony Rich
Watch Now:Apple TV