The Big Bang Theory (2007– )
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The Bath Item Gift Hypothesis 

Leonard is disappointed when Penny develops an interest in an attractive physicist at the university. Meanwhile, Sheldon struggles to find an appropriate Christmas gift for Penny.



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Sheldon is angry at Penny because she bought him a Christmas gift. Sheldon now feels he has to reciprocate and go through the trouble of buying something for someone he doesn't really understand, all at the same price of the gift he is about to receive. Meanwhile, David Underhill, last year's MacArthur grant award winner based on his work which has basically rendered Leonard's recent work meaningless, is a new addition to the Physics department at Cal Tech. Regardless, Leonard is enthralled to be working with Dave, who is not only good looking, but Leonard learns is a Renaissance man. Upon their meeting, Dave is attracted to Penny, and vice versa, and they decide to date. Penny even pretends to be a science geek to impress him. Leonard is angry at Penny's hypocrisy, since she was scared that Leonard was too smart for her to date. Penny, however, has some more important news about her relationship with Dave. Written by Huggo

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Comedy | Romance


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15 December 2008 (USA)  »

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Did You Know?


The Diet Coke can on the lunch table in the first scene has been altered to read "Diet Cola". See more »


In the beginning of the episode, Dave Underhill entered the cafeteria scene and sat with a group of people. During the scene, he changes seat 3 times within a 15 second span. See more »


[first lines]
Sheldon Cooper: Your argument is lacking in all scientific merit. Now, it is well established Superman cleans his by flying into Earth's yellow sun, which incinerates any contaminant matter and leaves the invulnerable kryptonian fabric unharmed and daisy-fresh.
Howard Wolowitz: What if he gets something kryptonian on it?
Sheldon Cooper: Like what?
Howard Wolowitz: I don't know. Kryptonian mustard.
Sheldon Cooper: I think we can safely assume all Kryptonian condiments were destroyed when the planet Krypton exploded.
Raj Koothrappali: Or it turned into mustard kryptonite, the only ...
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Crazy Credits

CHUCK LORRE PRODUCTIONS, #233 Recently the magazine Entertainment Weekly had an article entitled the "The 25 Smartest People in Television." Yours truly was ranked at number twenty. If the article is to be taken seriously, and God knows, why wouldn't any sensible person take it seriously, that means there are currently nineteen people in the TV biz who are smarter than me. Now I'm just thinking out loud here, but if something were to happen to those nineteen people... if say, they were to, one by one, have horrible accidents, or mysteriously disappear, then that would make me, ipso facto, the number one smartest person in television. Then I'd just have to keep an eye on number twenty-one. Christina Wayne, Senior VP of original programming at AMC, looks like the kind of woman who would stop at nothing to move up a spot. See more »


Features Wii Sports (2006) See more »


The Big Bang Theory Theme (Instrumental)
Composed and Performed by Barenaked Ladies
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"I Possess The DNA Of Leonard Nimoy?"
31 March 2015 | by (Fredericksburg, VA) – See all my reviews

"The Bath Item Gift Hypothesis" was the eleventh episode of the second season of the American sitcom 'The Big Bang Theory', directed by Mark Cendrowski and written by Bill Prady and Richard Rosenstock. Airing on December 15, 2008, and viewed by 11.42 million people, it was Jim Parsons that submitted the episode for consideration due to his nomination for the Primetime Emmy Awards for Outstanding Lead Actor in a Comedy Series at the 61st Primetime Emmy Awards. Strictly adhering to routine, along with his trademark irony and sarcasm, theoretical physicist Dr. Sheldon Cooper (Jim Parsons) worries about the vastly approaching Christmas holidays, since he does not celebrate it. His indecision about what to give his blonde waitress and aspiring actress neighbor across the hall Penny (Kaley Cuoco) as a gift bothers him. Penny asks if he and the guys are putting up a Christmas tree in their apartment, to which Sheldon replies, "We do not celebrate the ancient pagan ritual of Saturnalia." Sheldon then explains, "In the pre-Christian era, as the winter solstice approached and the plants died, pagans brought evergreen boughs into their homes as an act of sympathetic magic to guard the plants and preserve their essences until spring. This custom was later appropriated by northern Europeans and eventually becomes the so-called Christmas tree." His friend Howard Wolowitz, a Jewish aerospace engineer that still lives with his mother, quips "And that, Charlie Brown, is what boredom is all about."

Seeing how Penny has already gotten him a gift, Sheldon, annoyed and upset instead of normally being accepting with the joys of the season, must return the favor posthaste, seeing her getting him a present in his mind equates an obligation. He must get her something of the same value based upon her present and perceived level of friendship. Sheldon ponders if obligations such as this are a contributing factor to the increased suicide rate during the holidays, as his friends, Dr. Rajesh "Raj" Koothrappali (Kunal Nayyar), an Indian astrophysicist, and Howard end up taking him to the mall. Deciding on a basket of bath items at the fictional store Le Bain Quotidien ('The Daily Bath'), a pun on the phrase 'le pain quotidien' (daily bread), he discovers a wide selection available, in which Sheldon sees as a "cacophonous assault of eucalyptus, bayberry, cinnamon and vanilla." Still unsure about what Penny is going to get him and what he should get her in return, he buys a barrage of bath baskets to cover all contingencies.

Meanwhile, Dr. Leonard Hofstadter (Johnny Galecki), Sheldon's roommate and experimental physicist, meets visiting researcher and fellow experiment physicist Dr. David Underhill (guest star Michael Trucco). Leonard envies David for being handsome, charming and cool. He is even a more successful physicist than Leonard is, though he still jumps at the offer to help David out with his research. However, Leonard's joy of hanging around David is inconveniently interrupted by envy when the latter encounters Penny. The twosome start dating, but they later separate when she discovers that he is married.

Penny's gift to Sheldon turns out to be a cloth napkin...having wiped his mouth and autographed by an off-screen Leonard Nimoy who just happened to be in the cafeteria downstairs! "To Sheldon: "Live Long and Prosper." Overwhelmed and speechless since the giddy geek Trekkie now possesses the televised Vulcan persona's DNA and can now grow his own Spock from just the help of a healthy ovum, Penny assures him that he's just getting the napkin. Sheldon, in turn, responds by giving Penny all of the gift baskets, followed by a rare, gingerly-given "Sheldon" hug, as Leonard claims it to be a "Saturnalia miracle" (i.e. Sheldon version of a Christmas miracle).

With holiday touches such as Wii Bowling Night and a hilarious explanation of how Superman cleans his uniform by flying into the Sun makes this Christmas episode about a handful of lone nerd geniuses set in Pasadena, California all the more festive. The TV Critic's Review says: "As a Christmas episode this definitely contains the feel good factor, but more than that it is the best episode this season. Combining character development and humor in a blend which this show can do really well." Chuck Lorre, the show's creator, was named in an article in the magazine Entertainment Weekly that year under "The 25 Smartest People In Television", ranking in at number twenty. A blurb from Lorre stated in the article says: "Now I'm just thinking out loud here, but if something were to happen to those nineteen people... if say, they were to, one by one, have horrible accidents, or mysteriously disappear, then that would make me, ipso facto, the number one smartest person in television." Seven years later, this episode still remains a modern Christmas comedy classic, though not completely clean for family viewings as many of the other episodes often employ sexual content or double entendres. And, in my personal opinion, the show is actually better than the full theme song sung by the Barenaked Ladies. Bazinga!

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