The Donation Oscillation – Penny tries to seduce an abstaining Leonard to ruin his “donation” for her ex-boyfriend, Zack, and his wife, Marissa. Also, Wolowitz, Bernadette, Anu and Koothrappali turn Koothrappali’s canceled bachelor party into a couple’s trip aboard the “vomit comet.”
The Meteorite Manifestation – Sheldon is thrilled to help Bernadette and Wolowitz navigate bureaucratic paperwork, until he discovers they are breaking the law. Also, Leonard is disappointed when his friends exclude him from a scientific project.
The Confirmation Polarization – Sheldon and Amy’s super asymmetry theory is proven by two physicists, Dr. Pemberton and Dr. Campbell from Chicago, who then try to kick Amy off the Nobel nomination. Also, Bernadette has a big success at work and Penny’s going to be a part of it—whether she wants to or not.
The Propagation Proposition – Penny’s ex-boyfriend, Zack, and his wife want a baby, but when Zack is infertile, they ask Leonard for help. Also, Koothrappali attempts to mend things with his ex-fiancée, Anu.
The Citation Negation – Sheldon and Amy are devastated after learning from a Russian paper that Super Asymmetry has already been discovered and disproven. Also, ultra-competitive Bernadette asks Stuart’s girlfriend, Denise, to teach her how to beat Howard in a popular videogame.
The Consummation Deviation – Sheldon tries to bond with Amy’s father, but when Wolowitz lures Mr. Fowler away with magic tricks, Sheldon has no choice but to bond with Mrs. Fowler. Also: Koothrappali and Anu try to get physical for the first time.
The Grant Allocation Derivation – Leonard is caught between a rock and a hard place when he’s responsible for distributing extra grant money. Also, Bernadette turns the backyard playhouse into a hideaway from her husband and kids.
The Planetarium Collision – Amy doesn’t have time to work on super-asymmetry, so Sheldon goes to great lengths to ensure she’s available to work with him even it if means accidentally sabotaging her career in the process. Also, Koothrappali doesn’t want Wolowitz to join him in hosting a show at the planetarium.
The Tam Turbulence – Sheldon won’t tell anyone why he’s never mentioned Tam, his childhood best friend, so Leonard takes matters into his own hands. Also, Bernadette and Penny take out Raj’s fiancée, Anu, for dinner to get the skinny on her.
The Procreation Calculation – The Wolowitzes’ life gets complicated when Stuart starts bringing his new girlfriend home. Also, Penny and Leonard talk about starting a family while Koothrappali explores an arranged marriage.