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Leonard & Sheldon Prepare For The Wedding
Watch The Big Bang Theory Season 5 Episode 24
"The Countdown Reflection"
Original Air Date:

The gang must hurry to plan a wedding when Howard and Bernadette decide to have the event before the NASA launch on the season finale of The Big Bang Theory.

Howard Must Reschedule
Watch The Big Bang Theory Season 5 Episode 23
"The Launch Acceleration"
Original Air Date:

With his NASA launch moved up, Howard's wedding must be rescheduled leaving him to deal with Bernadette's family on The Big Bang Theory.

Penny, Amy, & Bernadette Read Unsettling News
Watch The Big Bang Theory Season 5 Episode 22
"The Stag Convergence"
Original Air Date:

Will Wheaton plays a party guest while Bernadette rethinks getting married on The Big Bang Theory.

Stephen Hawking on The Big Bang Theory
Watch The Big Bang Theory Season 5 Episode 21
"The Hawking Excitation"
Original Air Date:

Wolowitz gets to work with Stephen Hawking this week, meaning Sheldon will do anything at all to meet his hero.

The Future Mrs. Koothrappali?
Watch The Big Bang Theory Season 5 Episode 20
"The Transporter Malfunction"
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Sheldon is haunted by Mr. Spock on this episode of The Big Bang Theory, as Leonard Nimoy guest voices.

Playing Video Games
Watch The Big Bang Theory Season 5 Episode 19
"The Weekend Vortex"
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Silly Sheldon. This Big Bang Theory character blows off Amy's aunt's birthday this week just to play video game.

What's Up with That Hair?
Watch The Big Bang Theory Season 5 Episode 18
"The Werewolf Transformation"
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Sheldon's barber gets sick this week, while astronaut training causes Wolowitz to rethink his decision to head into space.

Pretty Painting
Watch The Big Bang Theory Season 5 Episode 17
"The Rothman Disintegration"
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Sheldon competes against Kripke this week for a job at the University, while a gift from Amy makes Penny uncomfortable.

Sheldon in the Lab
Watch The Big Bang Theory Season 5 Episode 16
"The Vacation Solution"
Original Air Date:

Sheldon tries to take a vacation this week, by working with Amy at her neurobiology lab. Howard, meanwhile, gets all worked up.

Really, Sheldon?!?
Watch The Big Bang Theory Season 5 Episode 15
"The Friendship Contraction"
Original Air Date:

Leonard reconsiders his friendship with Sheldon this week due to the latter's demands. Elsewhere, NASA astronaut Mike Massimino as himself.

Fun with Flags
Watch The Big Bang Theory Season 5 Episode 14
"The Beta Test Initiation"
Original Air Date:

Leonard and Penny experiment with dating again this week, while Raj develops an odd connection with his phone's virtual assistant.

A Romantic Evening
Watch The Big Bang Theory Season 5 Episode 13
"The Recombination Hypothesis"
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Leonard asks Penny out on a date this week, causing everyone else to wonder how life might change it it goes well. It's the show's 100th episode!

The Big Bang Theory Boys
Watch The Big Bang Theory Season 5 Episode 12
"The Shiny Trinket Maneuver"
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Sheldon isn't sufficiently impressed by Amy's accomplishment on The Big Bang Theory this week, while Howard must be okay with Bernadette disliking kids.

The Big Bang Theory Trio
Watch The Big Bang Theory Season 5 Episode 11
"The Speckerman Recurrence"
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Leonard comes face to face wit his high school bully this week. The latter is played by Lance Barber.

A New Man for Amy?
Watch The Big Bang Theory Season 5 Episode 10
"The Flaming Spittoon Acquisition"
Original Air Date:

Sheldon grows jealous of Amy dating someone else this week. That other man is Stuart from the comic book store.

Just the Two of Us
Watch The Big Bang Theory Season 5 Episode 9
"The Ornithophobia Diffusion "
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Leonard and Penny try to actually hang out alone this week. Meanwhile, Sheldon faces his fear of birds.

Amy in Action
Watch The Big Bang Theory Season 5 Episode 8
"The Isolation Permutation"
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Bernadette and Penny go shopping for a wedding dress on The Big Bang Theory this week. Without Amy!

A Good Scare
Watch The Big Bang Theory Season 5 Episode 7
"The Good Guy Fluctuation"
Original Air Date:

A comic book artist comes between Leonard and Priya this week. Elsewhere, Sheldon has a goal: scare his pals on Halloween.

Laurie Metcalf on The Big Bang Theory
Watch The Big Bang Theory Season 5 Episode 6
"The Rhinitis Revelation"
Original Air Date:

Laurie Metcalf comes on board this episode of The Big Bang Theory. She plays Sheldon's mother.

Party with Wil Wheaton
Watch The Big Bang Theory Season 5 Episode 5
"The Russian Rocket Reaction"
Original Air Date:

Wil Wheaton returns and hosts a party this week. Sheldon and Leonard are invited. Read on for a recap.

The Men of The Big Bang Theory
Watch The Big Bang Theory Season 5 Episode 4
"The Wiggly Finger Catalyst"
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Raj meets a girl this week! One with whom he actually communicate!

The Pulled Groin Extrapolation Scene
Watch The Big Bang Theory Season 5 Episode 3
"The Pulled Groin Extrapolation"
Original Air Date:

How will Sheldon and Penny get along this week, with Leonard off at a wedding with Amy? That's the main Big Bang Theory question.

The Infestation Hypothesis Photo
Watch The Big Bang Theory Season 5 Episode 2
"The Infestation Hypothesis"
Original Air Date:

Amy is caught in the middle this week, as Sheldon and Penny fight. Leonard, meanwhile, tries to spice things up with Priya.

Amy vs. Penny
Watch The Big Bang Theory Season 5 Episode 1
"The Skank Reflex Analysis"
Original Air Date:

The Big Bang Theory is back! On the premiere, the gang deals with Penny and Raj actually sleeping together.

The Big Bang Theory Season 5 Quotes

Sheldon: Professor Hawking, it's an honor and a privilege to meet you, sir.
Stephen Hawking: I know.

You can't blame yourself. When your prefrontal cortex fails to make you happy promiscuity rewards you with the needed flood of dopamine. We, neurobiologists, refer to this as the skank reflex.

Amy
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