Top Five Episodes of "The Big Bang Theory"

"The Big Bang Theory" is a sitcom that began airing in 2007 on CBS. The show features 4 brilliant, but nerdy, scientists. Two of these scientists, Sheldon Cooper and Leonard Hofstadter, both work at Caltech and share an apartment. Across the hall, their neighbor Penny is a pretty waitress who doesn't share the guys' cerebral interests.

"The Big Bang Theory" features smart but accessible humor, leading it to become one of the most popular sitcoms in recent years. The show has a devoted fan base, including a large contingent of so-called "nerds" who share interests with its characters. According to fans who've voted on the show at TV.com, these are the top five episodes of "The Big Bang Theory."

#5 "The Dumpling Paradox"

Penny's promiscuous friend Christy visits from Nebraska, and promptly sleeps with Howard. Howard later invites Christy to move in with him and his mother. Penny winds up sleeping at Leonard and Sheldon's apartment, and takes Howard's place while the group plays Halo 3. Sheldon becomes upset at how good Penny is at the game, as she manages to blow his head off in just the first few moments of gameplay.

Best Quote: Leonard: "Y'know Penny, we make such a good team, maybe we could enter a couple of Halo tournaments sometime." Penny: "Or we could just have a life."

#4 "The Grasshopper Experiment"

This is the first episode where Raj's parents are seen via webcam. Raj becomes frustrated when his parents try to set him up on a date, since he believes he can't talk to women and doesn't want to wind up in an unhappy arranged marriage. Meanwhile, Penny's learning to tend bar at the restaurant where she works and invites the guys to come help her practice. Raj agrees to have his date at the restaurant, so that his friends can watch. After a few drinks, Raj loosens up enough to talk but becomes obnoxious. Raj's date becomes interested in Sheldon after he tells her she looks like an Indian princess from a favorite childhood story.

Best Quote: Leonard: "Do you really need the Honorary Justice League of America membership card?" Sheldon: "It's been in every wallet I've owned since I was 5." Leonard: "Why?" Sheldon: "It says, 'Keep this on your person at all times.' It's right here under Batman's signature."

#3 "The Middle Earth Paradigm"

Penny invites the guys to her Halloween party. They initially refuse, but agree to go after remembering they can wear costumes. They all dress up as The Flash, leading to the argument that they should have had a "costume meeting." After costume changes, Leonard dresses as Frodo Baggins, Howard goes as Robin Hood (but gets mistaken for Peter Pan), Raj goes as Thor, and Sheldon dresses as the Doppler Effect - and subsequently gets upset that no one knows what his costume is. Leonard leaves after seeing Penny's ex-boyfriend Kurt has been invited. Penny's upset as he leaves, but kisses him before going back to the party.

Best Quote: Leonard (to Kurt, after kissing Penny): "That's right. You saw what you saw. That's how we roll in the Shire."

#2 "The Zazzy Substitution"

Sheldon's relationship with neurobiologist Amy Farrah Fowler is very annoying to the other guys. Since she's essentially a female version of Sheldon, the others can't stand to be around them together. After an argument over lunch, the two agree to "terminate" their relationship "immediately." Leonard, Howard and Raj are initially relieved, until Sheldon starts acting stranger than usual. Sheldon then starts collecting cats, eventually adopting 25 before Leonard calls Sheldon's mother for help. By the end of the episode, Sheldon and Amy reconcile and sell his cats for $20 each.

Best Quote: Sheldon (after rattling off names of cats named after scientists): "I was going to name him Hermann von Helmholtz, but he's so...zazzy."

#1 "The Big Bran Hypothesis"

Leonard and Sheldon go to Penny's apartment to drop off some Ikea-like furniture that was delivered for her. Sheldon becomes upset at how messy Penny's apartment is, and sneaks into her apartment later that night to clean. Leonard reluctantly helps, and Penny temporarily bans them both from her apartment when she finds out. Though this was the second episode of the show to be aired, it's technically show #3. Before the actors playing Penny, Raj and Howard were hired, an earlier pilot had been filmed. This pilot was never aired, but the show's creators say it could end up on a DVD release.

Best Quote: Sheldon: "Oh gravity, thou art a heartless bitch."

This is just one source of data on the most popular episodes of "The Big Bang Theory." 4 of the 5 listed are from the show's first season, and fan favorites like "The Lizard-Spock Expansion" (which birthed the show's game, "rock-paper-scissors-lizard-Spock") are mysteriously absent. For new converts to the show, however, TV.com's list remains a good place to see the best "The Big Bang Theory" has to offer.

Sources:

"'The Big Bang Theory' Most Popular Episode Guide." TV.com.