Season 5
🎬 24 Episodes 📅 2011 ⏱ 22 min
When an aspiring actress moves into the apartment next door, she inadvertently becomes the missing link in The Big Bang Theory's carefully constructed world of equations and comic books. Sheldon's rigid routines and Leonard's awkward charm collide head-on with her infectious energy, creating an unlikely dynamic that neither group expected. As Howard and Raj watch this clash of personalities unfold, they realize their insular circle might actually benefit from an outsider's perspective. What begins as neighborly annoyance transforms into genuine friendship, proving that sometimes the best connections happen when different worlds unexpectedly collide.
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📊 Season Stats
24
Episodes
2011
Year
22
min / ep
8.8
Watch Hours
5/12
Season No.
⭐ 7.9
Best Episode
Ep. 24 · The Countdown Reflecti…
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🎬 Episodes 24 episodes
1
⭐ 7.5
The Skank Reflex Analysis
Penny is worried with how damaged her friendship with the guys will be in the aftermath of her sleeping with Raj while Sheldon becomes the leader of the paintball team.
🎬 Mark Cendrowski ✍️ Maria Ferrari
2
⭐ 7.7
The Infestation Hypothesis
A fight between Sheldon and Penny leaves Amy caught in the middle, while Leonard tries to spice up his long-distance relationship with Priya.
🎬 Mark Cendrowski ✍️ Steven Molaro
3
⭐ 7.3
The Pulled Groin Extrapolation
Leonard and Amy get to know each other better, while Howard and Bernadette spend the weekend with Mrs. Wolowitz.
🎬 Mark Cendrowski ✍️ Chuck Lorre
4
⭐ 7.4
The Wiggly Finger Catalyst
Penny plays Matchmaker for Raj, which results in him finding a girl he is comfortable talking to.
🎬 Mark Cendrowski ✍️ Chuck Lorre
5
⭐ 7.6
The Russian Rocket Reaction
Sheldon and Leonard get invited to a party at Wil Wheaton's house, and Howard gets an out-of-this-world opportunity.
🎬 Mark Cendrowski ✍️ Steven Molaro
6
⭐ 7.4
The Rhinitis Revelation
Sheldon's mother, Mary Cooper, comes to visit, but Sheldon is annoyed that she also spends time with the rest of the gang, instead of catering to his every demand.
🎬 Howard Murray ✍️ Chuck Lorre
7
⭐ 7.6
The Good Guy Fluctuation
A cute comic book artist puts Leonard and Priya’s relationship to the test, while Sheldon tries to scare the guys for Halloween.
🎬 Mark Cendrowski ✍️ Chuck Lorre
8
⭐ 7.3
The Isolation Permutation
Amy becomes heartbroken when she discovers that Penny and Bernadette went wedding dress shopping without her.
🎬 Mark Cendrowski ✍️ Chuck Lorre
9
⭐ 7.4
The Ornithophobia Diffusion
Leonard and Penny try hanging out as friends on a 'non-date', but end up purposely ruining each others chances with perspective dates. Meanwhile, Sheldon enlists the help of Bernadette and Amy to overcome his fear of birds.
🎬 Mark Cendrowski ✍️ Chuck Lorre
10
⭐ 7.2
The Flaming Spittoon Acquisition
When Stuart asks Amy out on a date, Sheldon must confront his feelings and consider where his relationship with Amy is going.
🎬 Mark Cendrowski ✍️ Chuck Lorre
11
⭐ 7.2
The Speckerman Recurrence
Leonard must face his fears after being contacted by his high school tormentor.
🎬 Anthony Rich ✍️ Chuck Lorre
12
⭐ 7.1
The Shiny Trinket Maneuver
Sheldon gets in trouble with Amy when he isn't impressed by her recent accomplishment, and Howard must come to grips with Bernadette's dislike of children.
🎬 Mark Cendrowski ✍️ Chuck Lorre
13
⭐ 7.6
The Recombination Hypothesis
Leonard, who broke up with Priya, asks Penny out to a spur-of the-moment romantic dinner for two, and the duo contemplates on their relationship.
🎬 Mark Cendrowski ✍️ Chuck Lorre
14
⭐ 7.6
The Beta Test Initiation
Leonard and Penny deal with the idea of starting a relationship again and Raj finally finds a "woman" he can talk to without being drunk, in the form of Siri on his new phone. Meanwhile, Sheldon decides to start a YouTube series entitled "Sheldon Cooper presents Fun with Flags" with the help of Amy.
🎬 Mark Cendrowski ✍️ Chuck Lorre
15
⭐ 7.2
The Friendship Contraction
Sheldon's selfish demands force Leonard to reconsider their friendship. Meanwhile, Wolowitz tries to pick his astronaut nickname.
🎬 Mark Cendrowski ✍️ Chuck Lorre
16
⭐ 6.9
The Vacation Solution
When Sheldon is forced to take his vacation, he goes to work with Amy in her neurobiology lab.
🎬 Mark Cendrowski ✍️ Chuck Lorre
17
⭐ 7.4
The Rothman Disintegration
Sheldon battles Kripke for a coveted office at the university. Penny receives a very unusual gift from Amy.
🎬 Mark Cendrowski ✍️ Chuck Lorre
18
⭐ 7.8
The Werewolf Transformation
Sheldon becomes agitated when his regular barber is out sick. Astronaut training causes Howard to reconsider wanting to go into space. Penny beats Leonard in chess, the first time she plays.
🎬 Mark Cendrowski ✍️ Chuck Lorre
19
⭐ 7.2
The Weekend Vortex
Sheldon must choose between joining Amy at her aunt's birthday party or playing videogames all weekend with the guys.
🎬 Mark Cendrowski ✍️ Chuck Lorre
20
⭐ 7.1
The Transporter Malfunction
Penny buys Leonard and Sheldon “Star Trek” collectibles as a thank-you, leading Sheldon to be haunted by Mr. Spock. Meanwhile, Raj decides he has met the “Future Mrs. Koothrappali” after his parents set him up on a date.
🎬 Mark Cendrowski ✍️ Chuck Lorre
21
⭐ 7.8
The Hawking Excitation
When Wolowitz gets to work with Stephen Hawking, Sheldon is willing to do anything to meet his hero.
🎬 Mark Cendrowski ✍️ Steven Molaro
22
⭐ 7.1
The Stag Convergence
After the guys throw Howard a bachelor party, Bernadette reconsiders marrying him after learning about his sexual history.
🎬 Peter Chakos ✍️ Eric Kaplan
23
⭐ 7.6
The Launch Acceleration
When NASA moves up Howard's mission, he must face his fears and Bernadette's dad, thus putting the wedding plans in jeopardy. Meanwhile, Leonard says something surprising to Penny in the bedroom.
🎬 Mark Cendrowski ✍️ Chuck Lorre
24
⭐ 7.9
The Countdown Reflection
The fifth season ends with Howard and Bernadette deciding to get married before his NASA mission, causing the gang to scurry into overdrive in an effort to stage the wedding. NASA astronaut Mike Massimino has a cameo as himself.
🎬 Mark Cendrowski ✍️ Eric Kaplan