This high-pitched, sarcastic scientist is Sheldon’s chief rival at Caltech and loves to mock his research
Barry Kripke
This iconic Star Trek actor, who played Captain Kirk, guest-starred as a celebrity guest at Wil Wheaton's D&D game
William Shatner
Leonard and Penny elope and officially get married in this neon-lit, 24-hour wedding city
Las Vegas
This is the specific apartment room number where Sheldon and Leonard live for the majority of the series
4A
When playing Rock, Paper, Scissors, the guys add two geeky options to lower the chance of ties: Lizard and this sci-fi character
Spock
This comic book shop owner is constantly depressed, financially broke, and relies on the guys to keep his business afloat
Stuart Bloom
This real-life tech billionaire and Tesla founder made a cameo appearance volunteering at a soup kitchen with Howard
Elon Musk
Sheldon surprises Amy by proposing to her in a New Jersey hotel room after another woman tries to do this to him
Kiss him (Dr. Ramona Nowitzki)
Penny's apartment door is located directly across the hall and features this specific room number
4B
Sheldon hosts an internet podcast dedicated entirely to the history, design, and trivia of these specific pieces of fabric
Flags (Fun with Flags)
This direct, deadpan scientist dated Leonard, went to high school with Bernadette, and plays the cello
Leslie Winkle
This legendary Marvel Comics creator filed a restraining order against Sheldon after Sheldon showed up at his house uninvited
Stan Lee
Howard and Bernadette find out they are expecting their first child, a baby girl whom they later name after this celestial object
Halley (like Halley's Comet)
The building's elevator famously broke because Leonard's rocket fuel experiment was about to explode, and Sheldon did this to save Leonard's life
Threw the fuel into the elevator / closed the doors
Howard uses his engineering skills to create a robotic device meant for the space station, but accidentally gets his own body part stuck in it
His hand (the robotic arm)
This tall, awkward geologist has a massive crush on Amy and brings Sheldon unique rocks as gifts
Bert Kibbler
This Star Wars actress, famous for playing Princess Leia, famously chased Sheldon with a baseball bat during a prank
Carrie Fisher
Raj famously overcomes his selective mutism and speaks to Penny without alcohol right after experiencing this sad relationship event
A breakup (with Lucy)
When Sheldon briefly moves out of apartment 4A, he rents a room from a strange, intense character played by this veteran actor
Christopher Lloyd
The guys stand in a grueling movie theater line for hours just to watch 21 minutes of footage added to this classic Indiana Jones film
Raiders of the Lost Ark
This is the name of Raj's dermatologist girlfriend, who shares his love for dark, gory horror movies
Emily Sweeney
This famous theoretical physicist, known for his work on black holes, frequently appeared as himself and became Sheldon's online Words with Friends rival
Stephen Hawking
To win back Amy's affection, Sheldon gifts her a sparkling version of this royal headpiece accessory
A tiara
According to the Roommate Agreement, this exact temperature is the mandatory setting for the apartment's thermostat
72 degrees
Sheldon invents a complex, frustrating role-playing card game named "Mystic Warlords of" this location
Ka'a