The Big Bang Theory Summary | The Big Bang Theory Website

Season 1 [2007–2008]

Pilot (101)

Brilliant physicists Leonard (Johnny Galecki) and Sheldon (Jim Parsons) are the kind of “beautiful minds” that understand how the universe works. But none of that genius helps them interact with people, especially women. All this begins to change when a free-spirited beauty named Penny (Kaley Cuoco) moves in next door. Sheldon, Leonard’s roommate, is quite content spending his nights playing Klingon Boggle with their socially dysfunctional friends, fellow Cal Tech scientists Wolowitz (Simon Helberg) and Koothrappali (Kunal Nayyar). However, Leonard sees in Penny a whole new universe of possibilities… including love. When Leonard and Sheldon meet new neighbor Penny, Leonard is excited, but Sheldon is less enthusiastic for he feels his friend is only chasing a dream he’ll never catch.

Original Air Date: September 24, 2007

The Big Bran Hypothesis (102)

Leonard volunteers to sign for a package, hoping to make a good impression on Penny. When he enlists the help of his obsessive-compulsive roommate, Sheldon, his attempt at chivalry goes horribly awry.

Original Air Date: October 1, 2007

The Fuzzy Boots Corollary (103)

Leonard is bummed to learn that his crush, Penny, is seeing someone, so encouraged by his friends and fellow scientists, Leonard actually summons the nerve to ask a woman (Guest Star Sara Gilbert) out on a date.

Original Air Date: October 8, 2007

The Luminous Fish Effect (104)

When Sheldon gets fired, he explores life beyond physics, but his initial thrill shopping with Penny devolves over time to him weaving ponchos as a shut-in, forcing Leonard to call on Sheldon’s mother (Guest Star Laurie Metcalf).

Original Air Date: October 15, 2007

The Hamburger Postulate (105)

After sensing his pursuit of Penny isn’t going anywhere, Leonard agrees to an unexpected sexual encounter with fellow scientist Leslie Winkle (Guest Star Sara Gilbert).

Original Air Date: October 22, 2007

The Middle Earth Paradigm (106)

Leonard, Sheldon, Wolowitz, and Koothrappali undertake a challenging and risky experiment-attending the Halloween party being thrown by their hot neighbor, Penny.

Original Air Date: October 29, 2007

The Dumpling Paradox (107)

When Wolowitz seduces Penny’s friend and takes over her apartment, Penny sleeps on Leonard and Sheldon’s couch. With Wolowitz preoccupied, the guys discover they are without a fourth member of their group and in desperation, they ask Penny to join their Halo team.

Original Air Date: November 5, 2007

The Grasshopper Experiment (108)

Koothrappali is overwhelmed after his parents arrange a blind date, but he discovers he actually can talk to the opposite sex after a few drinks; however, complications set in when his beautiful date is more interested in Sheldon.

Original Air Date: November 12, 2007

The Cooper-Hofstadter Polarization (109)

When Sheldon and Leonard are invited to present their joint findings at a physics conference, Sheldon refuses, and Penny steps in to mediate, only deepening the rift between the two best friends.

Original Air Date: March 17, 2008

The Loobenfeld Decay (110)

After hearing Penny sing, Leonard lies to avoid seeing her perform, but Sheldon takes it one step further with a more elaborate lie that leads to the appearance of his non-existent cousin. D.J. Qualls (“Road Trip”) Guest Stars.

Original Air Date: March 24, 2008 | Recap

The Pancake Batter Anomaly (111)

When Sheldon gets sick, Leonard and the boys know what’s in store and avoid him like the plague, leaving an unsuspecting Penny to nurse the world’s worst patient back to health.

Original Air Date: March 31, 2008

The Jerusalem Duality (112)

When Leonard and Sheldon meet a 15-year-old physics prodigy (Guest Star Austin Lee), Sheldon is distraught that this boy genius is younger and smarter, so in an attempt to restore his sense of purpose, the boys come up with a solution to derail Dennis’ research.

Original Air Date: April 14, 2008

The Bat Jar Conjecture (113)

Since Sheldon’s only focus is to prove his mental superiority while preparing for the Physics Bowl, the guys kick him off the team and enlist his nemesis Leslie Winkle (Guest Star Sara Gilbert).

Original Air Date: April 21, 2008

The Nerdvana Annihilation (114)

When Leonard and the guys buy a time machine prop from a classic 1960 movie, its arrival creates problems for Penny and she tells the boys that their obsession with comics and toys is “pathetic.”

Original Air Date: April 28, 2008 | Recap

The Shiksa Indeterminacy (115)

When Leonard, Wolowitz, and Koothrappali all become smitten with Sheldon’s twin sister, Leonard devises a plan to eliminate his rivals. However, it backfires when Sheldon declares he will decide whom his sister dates.

Original Air Date: May 5, 2008

The Peanut Reaction (116)

When Penny learns that Leonard doesn’t celebrate birthdays, she attempts to throw him a surprise party, but is sidetracked by Sheldon, who unexpectedly gets to live out one of his greatest fantasies at an electronics store.

Original Air Date: May 12, 2008 | Recap

The Tangerine Factor (117)

When Leonard asks Penny out on a date and she says yes, they each seek the “wisdom” of reluctant advisor Sheldon.
[FIRST-SEASON FINALE]

Original Air Date: May 19, 2008