Out of circumstance, Leonard admits to Sheldon that he still has in his possession a DVD rental from seven years ago that was under Sheldon's name, and that Leonard was s ...

Leonard, Sheldon and Amy run into Leonard and Sheldon's childhood hero Arthur Jeffries, aka Professor Proton, the scientist host of their favorite childhood television pr ...

The anniversary of Howard and Bernadette's first date is approaching, and Howard wants to do something special and romantic for the occasion, namely write a song for her ...

Amy has the opportunity to work on a project at Cal Tech for a couple of months, which means that she and Sheldon would be at the same workplace. To her surprise, Sheldon ...

For her Psychology class, Penny has on the recommended reading list one of Leonard's mother's books. Leonard doesn't want Penny to read it, and all about his troubled chi ...

The gang, after rebuking Raj's attempt of a social gathering in the form of a murder mystery dinner party, are surprised that they actually like Raj's latest idea: an int ...

Leonard has come home a few days early, surprising Penny. The one person who isn't surprised is Sheldon, as Leonard hasn't told him and doesn't want him to know so that h ...

Bernadette and Amy are attending a conference together. Despite being without their regular third, they end up not talking about science but boys like they would usually ...

Howard thinks that Leonard has a good shot at one of the positions working for Stephen Hawking on a four month long expedition on a ship in the North Sea. Leonard is exci ...

While the girls are in Las Vegas drinking and carousing, the boys are playing Dungeons and Dragons. The weekend doesn't turn out quite the way each group expects. The boy ...

Sheldon has just located his childhood hero, Arthur Jeffries Ph.D., online. He was better known as Professor Proton, host of a children's science show. Both Sheldon and L ...

Sheldon has just learned that his favorite television show, Alphas (2011) has been canceled after two seasons on the air. What's inconceivable about the situation is that ...

The death of Professor Tupperman at Cal Tech opens up a tenured position. Leonard, Sheldon, Raj and Kripke each have different reasons for wanting the tenure opening. The ...

Howard's idea of cleaning up in preparation for a dinner party at their place is to throw everything into the closet, which irks Bernadette. Howard suggests that if Berna ...

The university requires that the guys promote science careers for women. Sheldon feels that they would be too late talking to college students and that they first try it ...

Raj and Lucy have coffee together after they meet at the comic book store and get along until she unexpectedly runs off. Raj gets depressed and won't leave his apartment. ...

Leonard, Penny, Howard and Bernadette go out to dinner on Valentine's Day where Penny sees a couple she despises and the woman is being proposed to. Leonard decides to do ...

After one insensitive and self-serving move too many by Sheldon, Leonard has had it with him and decides to move out, even throwing the roommate agreement into the garbag ...

Sheldon and Barry Kripke are both working on grant proposals for the same thing. As the university can only submit one proposal, they make Sheldon and Kripke work togethe ...

The guys are off to a Comic-Con in Bakersfield. On the way they decide to stop at Vasquez Rocks where many Star Trek episodes were filmed and take some pictures of their ...

A surprised Leonard finally comes to the realization that Sheldon's assistant, Alex, is attracted to him. As he believes it negatively affects him since Alex is not focus ...

Much to Penny, Bernadette and Amy's chagrin, Leonard organizes a boys only Saturday night get together for himself, Sheldon, Howard, Raj and Stuart to play a holiday them ...

Howard isn't looking forward to the dinner he and Bernadette are having at her parent's house. In particular, he and Bernadette's father, with who Bernadette would really ...

Howard finally replaces his scooter with a car and is assigned a parking spot at Caltech. Unfortunately it's Sheldon's spot even though he doesn't own a car or drive. A w ...

Howard has noticed that Sheldon disappears for exactly twenty minutes every afternoon at exactly the same time without telling anyone where he's going or what he's doing. ...

Sheldon decides to tape a special Fun With Flags episode about Star Trek flags, and invites his friend, Wil Wheaton to be a guest star. During the taping Amy, who is in d ...

Sheldon and Stephen Hawking begin playing a popular online game Words with Friends. When he stops responding to their game, Sheldon begins obsess about being ignored. Mea ...

Stuart decides to organize a Halloween party at his comic book store so Raj decides to become the party planner. At the encouragement of Amy and Bernadette, Penny decides ...

Howard returns to Earth feeling dejected when he finds out that his friends are not waiting for him at the airport at the request of Bernadette, who wants to spend some q ...

Sheldon needs someone to read through the works he did during his elementary school days, to find out if he has made a scientific breakthrough that was Nobel Prize worthy ...

Penny tries to figure out what her feelings for Leonard are, since she is happy with their relationship, yet she is unsure if she is in love just yet. She confides in Ber ...

On the occasion of the second anniversary of their first date Sheldon and Amy celebrate, however a lonely Raj is invited by Sheldon to join them. Amy is quite upset by Sh ...