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The Big Bang Theory Season 5 Episodes
Season 5 Episode Guide
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 realises what she's done by sleeping with Raj; and Sheldon becomes the leader of the paintball team.
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.
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.
Episode 4
The Wiggly Finger Catalyst
Thu, Oct 6, 2011 30 mins
Raj meets a woman with whom he's able to talk.
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.
Episode 6
The Rhinitis Revelation
Thu, Oct 20, 2011 30 mins
Sheldon's mother visits, and he competes for her attention, which seems more focused on his friends.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
Episode 18
The Werewolf Transformation
Thu, Feb 23, 2012 30 mins
After his barber is hospitalised, 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.
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.
Episode 20
The Transporter Malfunction
Thu, Mar 29, 2012 30 mins
Raj may have found his soulmate 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 after he breaks Leonard's "Star Trek" collectible.
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.
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.
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.
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.