The Big Bang Theory

Episodes

Season 5 · 24 episodes

• E1 The Skank Reflex Analysis
  Sep 22, 2011 25 min

  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.

• E2 The Infestation Hypothesis
  Sep 22, 2011 25 min

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

• E3 The Pulled Groin Extrapolation
  Sep 29, 2011 25 min

  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.

• E4 The Wiggly Finger Catalyst
  Oct 6, 2011 25 min

  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.

• E5 The Russian Rocket Reaction
  Oct 13, 2011 25 min

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

• E6 The Rhinitis Revelation
  Oct 20, 2011 25 min

  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.

• E7 The Good Guy Fluctuation
  Oct 27, 2011 25 min

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

• E8 The Isolation Permutation
  Nov 3, 2011 25 min

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

• E9 The Ornithophobia Diffusion
  Nov 10, 2011 25 min

  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.

• E10 The Flaming Spittoon Acquisition
  Nov 17, 2011 25 min

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

• E11 The Speckerman Recurrence
  Dec 8, 2011 25 min

  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.

• E12 The Shiny Trinket Maneuver
  Jan 12, 2012 25 min

  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.

• E13 The Recombination Hypothesis
  Jan 19, 2012 25 min

  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.

• E14 The Beta Test Initiation
  Jan 26, 2012 25 min

  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.

• E15 The Friendship Contraction
  Feb 2, 2012 25 min

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

• E16 The Vacation Solution
  Feb 9, 2012 25 min

  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.

• E17 The Rothman Disintegration
  Feb 16, 2012 25 min

  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.

• E18 The Werewolf Transformation
  Feb 23, 2012 25 min

  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.

• E19 The Weekend Vortex
  Mar 8, 2012 25 min

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

• E20 The Transporter Malfunction
  Mar 29, 2012 25 min

  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.

• E21 The Hawking Excitation
  Apr 5, 2012 25 min

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

• E22 The Stag Convergence
  Apr 26, 2012 25 min

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

• E23 The Launch Acceleration
  May 3, 2012 25 min

  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.

• E24 The Countdown Reflection
  May 10, 2012 25 min

  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.