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The Big Bang Theory Season 3 Episodes

23 Episodes 2009 - 2010

The sitcom's third season begins with the guys returning from the North Pole, and Leonard (Johnny Galecki) and Penny (Kaley Cuoco) enthusiastically jump-starting their relationship. Meanwhile, Howard (Simon Helberg) begins dating Penny's coworker Bernadette (Melissa Rauch). Wil Wheaton appears as an archnemesis of Sheldon (Jim Parsons); and Marvel comics creator Stan Lee has memorable cameo appearance. Kunal Nayyar also stars.

Episode 1

The Electric Can Opener Fluctuation

Mon, Sep 21, 2009 30 mins

In the third-season opener, Sheldon feels betrayed when his friends alter his arctic-expedition data, so he takes off for Texas. The guys follow him, which kills Leonard's chance for a romantic meeting with Penny.

Where to Watch
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Episode 2

The Jiminy Conjecture

Mon, Sep 28, 2009 30 mins

Sheldon and Howard consult an entomologist (Lewis Black) to help settle a bet---with their favorite comic books at stake---regarding a species of cricket. Meanwhile, Leonard and Penny try to figure out what's next after an awkward first attempt at intimacy.

Where to Watch
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Episode 3

The Gothowitz Deviation

Mon, Oct 5, 2009 30 mins

Sheldon tries to change Penny through behavior modification, using chocolate as motivation. Meanwhile, Howard and Raj try to pick up women at a Goth nightclub.

Where to Watch
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Episode 4

The Pirate Solution

Mon, Oct 12, 2009 30 mins

Raj needs to find a new job or he will be sent back to India, so Sheldon hires Raj to work for him. Meanwhile, Leonard and Penny need to explain the "three's company" concept to Howard.

Where to Watch
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Episode 5

The Creepy Candy Coating Corollary

Mon, Oct 19, 2009 30 mins

Sheldon enters a trading-card competition when he hears Wil Wheaton (in a cameo), for whom he harbors resentment, is also participating. Meanwhile, Wolowitz asks Penny to set him up with one of her friends.

Where to Watch
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Episode 6

The Cornhusker Vortex

Mon, Nov 2, 2009 30 mins

Sheldon tries to teach Leonard the fundamentals of football, while Raj and Howard quarrel over an incident involving kites.

Where to Watch
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Episode 7

The Guitarist Amplification

Mon, Nov 9, 2009 30 mins

Leonard and Penny fight, and Sheldon mediates.

Where to Watch
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Episode 8

The Adhesive Duck Deficiency

Mon, Nov 16, 2009 30 mins

After the guys, except for Sheldon, go camping, Penny is injured and left with only Sheldon to come to her rescue.

Where to Watch
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Episode 9

The Vengeance Formulation

Mon, Nov 23, 2009 30 mins

Sheldon is humiliated on National Public Radio and vows vengeance on Kripke; and Wolowitz begins a relationship with Katee Sackhoff, who appears in a cameo. Ira Flatow also makes a cameo appearance.

Where to Watch
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Episode 10

The Gorilla Experiment

Mon, Dec 7, 2009 30 mins

Sheldon tries to teach Penny physics so she'll understand Leonard's work; Wolowitz is jealous when Leonard bonds with his girlfriend.

Where to Watch
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Episode 11

The Maternal Congruence

Mon, Dec 14, 2009 30 mins

Leonard's mother visits, which pleases Sheldon but upsets Leonard.

Where to Watch
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Episode 12

The Psychic Vortex

Mon, Jan 11, 2010 30 mins

Sheldon helps Koothrappali pick up women at a university mixer; and Leonard is shocked to learn that Penny believes in psychics. Abby: Danica McKellar.

Where to Watch
The Big Bang Theory, Season 3 Episode 12 image

Episode 13

The Bozeman Reaction

Mon, Jan 18, 2010 30 mins

Leonard and Sheldon's apartment is robbed, so they create an elaborate security system with the help of their friends.

Where to Watch
The Big Bang Theory, Season 3 Episode 13 image

Episode 14

The Einstein Approximation

Mon, Feb 1, 2010 30 mins

Newton had his apple. Sheldon has cheesecake. An impasse in his work leads Sheldon to get a job working with Penny at a restaurant known for that dessert.

Where to Watch
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Episode 15

The Large Hadron Collision

Mon, Feb 8, 2010 30 mins

Leonard is only allowed to bring one guest for his trip to the CERN science complex in Switzerland, and he's forced to choose between Sheldon and Penny.

Where to Watch
The Big Bang Theory, Season 3 Episode 15 image

Episode 16

The Excelsior Acquisition

Mon, Mar 1, 2010 30 mins

Sheldon misses an opportunity to meet comics mogul Stan Lee, who appears in a cameo, when he has to go to traffic court after getting a ticket because of Penny.

Where to Watch
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Episode 17

The Precious Fragmentation

Mon, Mar 8, 2010 30 mins

The guys go to a garage sale and find a ring from "The Lord of the Rings" film, and the rare find threatens their friendship.

Where to Watch
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Episode 18

The Pants Alternative

Mon, Mar 22, 2010 30 mins

The friends try to help Sheldon overcome his fear of speaking in public.

Where to Watch
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Episode 19

The Wheaton Recurrence

Mon, Apr 12, 2010 30 mins

Wil Wheaton returns and once again battles with Sheldon, this time in a bowling match; and Penny and Leonard have a fight that threatens their relationship.

Where to Watch
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Episode 20

The Spaghetti Catalyst

Mon, May 3, 2010 30 mins

Sheldon tells a lie to appease Penny and Leonard, who aren't speaking to each other, but then he gets caught.

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Episode 21

The Plimpton Stimulation

Mon, May 10, 2010 30 mins

The arrival of a famous physicist, has Sheldon and Leonard competing for her attention.

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Episode 22

The Staircase Implementation

Mon, May 17, 2010 30 mins

Leonard tells Penny the story of how he met Sheldon.

Where to Watch
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Episode 23

The Lunar Excitation

Mon, May 24, 2010 30 mins

In the third-season finale, Wolowitz and Koothrappali play matchmaker for Sheldon by setting up an online-dating profile for him. Meanwhile, Penny thinks that her relationship with Leonard has affected her ability to date "normal" men.

Where to Watch
The Big Bang Theory, Season 3 Episode 23 image