Series / The Big Bang Theory
Yes, this is a picture from a show named after the event that created the universe.note 

Leonard: Okay, well, I'm an experimental physicist at Caltech. Most of my research involves high powered lasers. Oh, and I just got a government grant to see if they can be used to knock out incoming ballistic missiles.
Penny: Wow! Can they?
Leonard: Oh God no! (long pause) But the money's good... and I used the equipment to build my own Bat Signal.

The Big Bang Theory is a CBS sitcom, created by Chuck Lorre, which made its debut in 2007, featuring four genius-level friends (with careers ranging from theoretical physics to engineering) and a pretty girl who shakes up their dependence on The Scientific Method and geeky lifestyle.

The main characters are two Odd Couple roommates, Dr. Leonard Hofstadternote  and Dr. Sheldon Coopernote . Leonard is a mild-mannered nerd who, although awkward, is still socially capable. Sheldon is an egomaniacal supergenius who displays signs of OCD, ADHD and many other Ambiguous Disorders.

A cute new neighbor named Pennynote  moves in next door, and Leonard almost instantly develops a crush on her. Penny is actually a perfectly normal person with an average intelligence level, but compared to Leonard and Sheldon comes across as a Dumb Blonde. On the other hand, she is very friendly and outgoing with a vibrant social life and a multitude of interests, contrasting the shy, reclusive personalities of the guys.

Rounding out the cast are two other genius geeks who are always visiting Sheldon and Leonard: Howard Wolowitznote , a wild but unsuccessful womanizer who never stops hitting on Penny; and Dr. Rajesh "Raj" Koothrappalinote , who suffers from crippling mutism whenever women are around (unless he's drunk).

The fourth season added two new female characters in semi-regular roles, who would eventually be promoted to the main cast: Dr. Bernadette Rostenkowskinote , a sweet-hearted microbiologist who is introduced as Penny's friend and co-worker, and soon formed a relationship with Howard; and Dr. Amy Farrah Fowlernote , a Distaff Counterpart to Sheldon who gradually became best friends with Penny and eased out of her neurotic shell. These two ended up forming a Power Trio with Penny that contrasts the four guys and gives a new female perspective on the show.

The show's humor can be divided into several categories: obscure references to physics or Geek culture, every nerd stereotype the writers can think of and the culture clash between Penny and the guys. Any given episode shuffles between romantic comedy/relationship drama, indulging in an established geeky pursuit and the work lives of the characters at Caltech. And, for the most part, the scientific and nerd references are accurate, or at least close enough that somewhere between the writing and the acting someone knows what they're talking about. The writers consult Dr. David Salzberg of UCLA for advice on scripts, dialogue and he personally maps out the white board equations.

As for the show's drama and overarching plot, most of that relies on Unresolved Sexual Tension between Leonard and Penny. The series almost runs on Give Geeks a Chance.

A transcript of episodes can be found here.

Now has a character sheet.

As of the 2017-2018 season, CBS premiered a spinoff show featuring the younger Sheldon, narrated by Jim Parsons.

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