The Electric Can Opener Fluctuation 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.
The Jiminy Conjecture 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.
The Gothowitz Deviation Howard and Raj visit a Goth nightclub to pick up women while Sheldon attempts to build a better Penny using chocolate-based behavior modification.
The Pirate Solution 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.
The Creepy Candy Coating Corollary 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.
The Cornhusker Vortex Sheldon teaches Leonard how to understand football while a kite-fighting incident threatens Howard and Raj's friendship.
The Adhesive Duck Deficiency With Leonard, Howard and Raj away camping in the desert, an injured Penny has only Sheldon to rely on.
The Vengeance Formulation After he's humiliated on National Public Radio Sheldon vows to destroy Kripke, while Wolowitz tries not to destroy his new relationship with Bernadette.
The Athens Recurrence Sheldon attempts to help Penny understand Leonard's work, and Wolowitz becomes jealous when Leonard starts hanging out with his new girlfriend.
The Maternal Congruence A visit from Leonard's mother delights Sheldon and horrifies Leonard.
The Psychic Vortex While Sheldon and Koothrappali attend a university mixer, Leonard is upset to discover that Penny believes in psychics.
The Bozeman Reaction When their apartment is robbed, Leonard and Sheldon turn to their friends to create a state-of-the-art security system.
The Einstein Approximation Sheldon's search for the answer to a physics problem leads him to work at the Cheesecake Factory with Penny.
The Large Hadron Collision Leonard can only bring one guest on a trip to see CERN's Large Hadron Collider (the world's largest and highest energy particle accelerator) in Switzerland on Valentine's Day.
