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The Big Bang Theory Season 5 Episodes

24 Episodes 2011 - 2012

Season 5 of the sitcom begins with the gang dealing with the aftermath of Penny (Kaley Cuoco) and Raj (Kunal Nayyar) sleeping together. Meanwhile, Leonard (Johnny Galecki) considers rekindling his relationship with Penny; Sheldon (Jim Parsons) and Amy (Mayim Bialik) take their relationship to the next level via a formal contract; and Howard (Simon Helberg) is commissioned to be an astronaut while also planning his wedding to Bernadette (Melissa Rauch).

Episode 1

The Skank Reflex Analysis

Thu, Sep 22, 2011 30 mins

In the fifth-season opener, Penny hits a low point when she realizes what she's done by sleeping with Raj; and Sheldon becomes the leader of the paintball team.

Where to Watch
The Big Bang Theory, Season 5 Episode 1 image

Episode 2

The Infestation Hypothesis

Thu, Sep 22, 2011 30 mins

Penny and Sheldon clash, and Amy is caught in the middle of their battle; and Leonard looks for ways to keep his long-distance romance with Priya alive.

Where to Watch
The Big Bang Theory, Season 5 Episode 2 image

Episode 3

The Pulled Groin Extrapolation

Thu, Sep 29, 2011 30 mins

Leonard is Amy's date for a wedding, giving Leonard a chance to get to know her better; and Howard and Bernadette spend a weekend with Mrs Wolowitz.

Where to Watch
The Big Bang Theory, Season 5 Episode 3 image

Episode 4

The Wiggly Finger Catalyst

Thu, Oct 6, 2011 30 mins

Raj meets a woman with whom he's able to talk.

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The Big Bang Theory, Season 5 Episode 4 image

Episode 5

The Russian Rocket Reaction

Thu, Oct 13, 2011 30 mins

Leonard and Sheldon attend a party at the home of Sheldon's nemesis, Wil Wheaton (in a cameo along with Brent Spiner).

Where to Watch
The Big Bang Theory, Season 5 Episode 5 image

Episode 6

The Rhinitis Revelation

Thu, Oct 20, 2011 30 mins

Sheldon's mom visits, and he competes for her attention, which seems more focused on his friends.

Where to Watch
The Big Bang Theory, Season 5 Episode 6 image

Episode 7

The Good Guy Fluctuation

Thu, Oct 27, 2011 30 mins

Leonard feels threatened when a charming comic-book artist comes between him and Priya; and Sheldon is determined to scare his friends on Halloween.

Where to Watch
The Big Bang Theory, Season 5 Episode 7 image

Episode 8

The Isolation Permutation

Thu, Nov 3, 2011 30 mins

Amy's heart is broken when Penny and Bernadette shop for wedding dresses and don't invite her.

Where to Watch
The Big Bang Theory, Season 5 Episode 8 image

Episode 9

The Ornithophobia Diffusion

Thu, Nov 10, 2011 30 mins

Leonard and Penny attempt to hang out alone; and Sheldon tries to overcome his fear of birds.

Where to Watch
The Big Bang Theory, Season 5 Episode 9 image

Episode 10

The Flaming Spittoon Acquisition

Thu, Nov 17, 2011 30 mins

Sheldon becomes jealous when Stuart from the comic-book store asks Amy out on a date, and Sheldon's forced to reconsider his relationship with Amy.

Where to Watch
The Big Bang Theory, Season 5 Episode 10 image

Episode 11

The Speckerman Recurrence

Thu, Dec 8, 2011 30 mins

Leonard confronts his fears when he's contacted by a bully who tormented him in high school.

Where to Watch
The Big Bang Theory, Season 5 Episode 11 image

Episode 12

The Shiny Trinket Maneuver

Thu, Jan 12, 2012 30 mins

Sheldon hurts Amy's feelings, and Penny gives him advice on how to be a better boyfriend; and Howard comes to terms with the fact that Bernadette isn't fond of children.

Where to Watch
The Big Bang Theory, Season 5 Episode 12 image

Episode 13

The Recombination Hypothesis

Thu, Jan 19, 2012 30 mins

More than food appears to be on the menu when Leonard invites Penny to a romantic dinner for two.

Where to Watch
The Big Bang Theory, Season 5 Episode 13 image

Episode 14

The Beta Test Initiation

Thu, Jan 26, 2012 30 mins

Leonard and Penny give dating another try, while Raj begins a rather unorthodox relationship with the virtual assistant on his phone.

Where to Watch
The Big Bang Theory, Season 5 Episode 14 image

Episode 15

The Friendship Contraction

Thu, Feb 2, 2012 30 mins

The friendship contract is in danger of being nullified when Leonard tires of Sheldon's selfish ways; Howard spaces out over selecting an astronaut nickname for himself.

Where to Watch
The Big Bang Theory, Season 5 Episode 15 image

Episode 16

The Vacation Solution

Thu, Feb 9, 2012 30 mins

Sheldon takes it easy by working with Amy at her neurobiology lab after the university orders him to take a vacation. Meanwhile, Howard gets worked up when Bernadette suggests they sign a prenuptial agreement.

Where to Watch
The Big Bang Theory, Season 5 Episode 16 image

Episode 17

The Rothman Disintegration

Thu, Feb 16, 2012 30 mins

Sheldon and Kripke square off in a series of sports-related competitions to win a coveted corner office at the university. Meanwhile, Penny feels uncomfortable accepting a gift from Amy.

Where to Watch
The Big Bang Theory, Season 5 Episode 17 image

Episode 18

The Werewolf Transformation

Thu, Feb 23, 2012 30 mins

After his barber is hospitalized, Sheldon undergoes a hair-raising change in lifestyle as his carefully planned daily routines are thrown for a loop. Meanwhile, Howard is up in the air about continuing his astronaut training.

Where to Watch
The Big Bang Theory, Season 5 Episode 18 image

Episode 19

The Weekend Vortex

Thu, Mar 8, 2012 30 mins

Sheldon opts to spend a weekend playing video games with the guys instead of attending a birthday party for Amy's aunt.

Where to Watch
The Big Bang Theory, Season 5 Episode 19 image

Episode 20

The Transporter Malfunction

Thu, Mar 29, 2012 30 mins

Raj may have found his soul mate after his parents set him up on a date. Meanwhile, Sheldon thinks he's going out of his mind when he begins hearing the voice of Spock (Leonard Nimoy) after he breaks Leonard's "Star Trek" collectible.

Where to Watch
The Big Bang Theory, Season 5 Episode 20 image

Episode 21

The Hawking Excitation

Thu, Apr 5, 2012 30 mins

Sheldon is in seventh heaven and prepared to do whatever it takes to meet his science idol Stephen Hawking, who is working on a project with Howard.

Where to Watch
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Episode 22

The Stag Convergence

Thu, Apr 26, 2012 30 mins

Bernadette has second thoughts about marrying Howard when details of his sexual history emerge at his bachelor party.

Where to Watch
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Episode 23

The Launch Acceleration

Thu, May 3, 2012 30 mins

When NASA reschedules the launch of Howard's mission, the countdown to his wedding with Bernadette is put on hold, leaving him to deal with an irate father of the bride. Meanwhile, Leonard's pillow talk with Penny leaves her steaming.

Where to Watch
The Big Bang Theory, Season 5 Episode 23 image

Episode 24

The Countdown Reflection

Thu, May 10, 2012 30 mins

The fifth season ends with Howard and Bernadette deciding to get married before his NASA mission, causing the gang to scurry into overdrive in an effort to stage the wedding.

Where to Watch
The Big Bang Theory, Season 5 Episode 24 image