The Big Bang Theory · Season 3
23 episodes listed, beginning 2009-09-21.
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- Episode 1
The Electric Can Opener Fluctuation
30 minutes
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Sheldon flees back to Texas in disgrace when he learns the guys tampered with his arctic expedition data, forcing the guys to follow him and threatening Leonard's hopes for a romantic encounter with Penny.
- Episode 2
The Jiminy Conjecture
30 minutes
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Leonard and Penny struggle to recover from an awkward first hookup while Sheldon and Howard stake their best comic books on a bet to determine the species of a cricket.
- Episode 3
The Gothowitz Deviation
30 minutes
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Howard and Raj visit a Goth nightclub to pick up women while Sheldon attempts to build a better Penny using chocolate-based behavior modification.
- Episode 4
The Pirate Solution
30 minutes
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Raj must find a new job or be sent back to India, but Sheldon has a solution, which leaves Leonard and Penny dealing with Howard as third wheel.
- Episode 5
The Creepy Candy Coating Corollary
30 minutes
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While Sheldon settles a score with his nemesis, Wil Wheaton, Wolowitz begs Leonard to get Penny to set him up with one of her friends.
- Episode 6
The Cornhusker Vortex
30 minutes
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Sheldon teaches Leonard how to understand football while a kite-fighting incident threatens Howard and Raj's friendship.
- Episode 7
The Guitarist Amplification
30 minutes
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An argument between Leonard and Penny proves "inconvenient" to Sheldon.
- Episode 8
The Adhesive Duck Deficiency
30 minutes
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With Leonard, Howard and Raj away camping in the desert, an injured Penny has only Sheldon to rely on.
- Episode 9
The Vengeance Formulation
30 minutes
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After he's humiliated on National Public Radio, Sheldon vows to destroy Kripke, while Wolowitz tries not to destroy his new relationship with Bernadette.
- Episode 10
The Gorilla Experiment
30 minutes
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Sheldon attempts to help Penny understand Leonard's work, and Wolowitz becomes jealous when Leonard starts hanging out with his new girlfriend.
- Episode 11
The Maternal Congruence
30 minutes
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Visit from Leonard's mother delights Sheldon and horrifies Leonard.
- Episode 12
The Psychic Vortex
30 minutes
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While Sheldon and Koothrappali attend a university mixer, Leonard is upset to discover that Penny believes in psychics.
- Episode 13
The Bozeman Reaction
30 minutes
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When their apartment is robbed, Leonard and Sheldon turn to their friends to create a state-of-the-art security system.
- Episode 14
The Einstein Approximation
30 minutes
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Sheldon's search for the answer to a physics problem leads him to work at the Cheesecake Factory with Penny.
- Episode 15
The Large Hadron Collision
30 minutes
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Leonard can only bring one guest on a trip to see CERN's Large Hadron Collider in Switzerland on Valentine's Day.
- Episode 16
The Excelsior Acquisition
30 minutes
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Sheldon winds up in traffic court when he gets a ticket because of Penny.
- Episode 17
The Precious Fragmentation
30 minutes
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When the guys find a ring from "The Lord of the Rings" at a garage sale, it threatens to tear them apart.
- Episode 18
The Pants Alternative
30 minutes
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Sheldon's friends come to his aid when his fear of public speaking stands between him and a coveted award.
- Episode 19
The Wheaton Recurrence
30 minutes
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Fight between Leonard and Penny threatens their relationship, while Sheldon battles Wil Wheaton in bowling.
- Episode 20
The Spaghetti Catalyst
30 minutes
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When Leonard and Penny aren't speaking, Sheldon goes to extremes to keep them both happy.
- Episode 21
The Plimpton Stimulation
30 minutes
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Leonard and Sheldon compete for the attention of a famous female physicist.
- Episode 22
The Staircase Implementation
30 minutes
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Leonard tells Penny about how he met Sheldon for the first time...and what happened to the elevator.
- Episode 23
The Lunar Excitation
30 minutes
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While Penny worries that dating Leonard has ruined her for normal guys, Wolowitz and Koothrappali search for Sheldon's perfect match online.
Original air-order information: TVmaze, CC BY-SA 4.0. Listed through September 10, 2026. Regular episodes only; specials and future air dates are not included.