Jim Parsons as Sheldon Cooper
Jim Parsons has been playing genius Caltech physicist Sheldon on the show since the first season. Sheldon is a proud nerd and thinks of himself as the perfect human specimen. He has a tendency of annoying many around him, with his lack of understanding of humor and his strict adherence to routine. He has been dating his neurobiologist girlfriend Amy since the 5th season, and officially proposed to her in season 10.
Jim Parsons- in high school
Just look at that adorable smirk and bowtie! Jim was born and raised in Houston, Texas. He lived with his mother and father, who were both school teachers, as well as his sister, who went on to become a teacher as well. Jim admired his parents’ jobs, but found a passion in acting. He attended Klein Oak High School where he participated and starred in nearly every theater production.
Mayim Bialik as Amy Fowler
The real-life neurobiologist and actress Mayim Bialik, also plays a neuroscientist on-screen, Amy. Amy was discovered by Raj and Howard on an online dating site and they matched her up with Sheldon. Although they had some bumps in the road, Amy is one of the only characters on the show who seems to really get Sheldon. Amy is part of Penny’s Posse, which includes Penny and Bernadette.
Mayim Bialik- in high school
Mayim Bialik is a California native, and attended North Hollywood High School. At the time, she was already a well-known actress and was starring in the ’90s series Blossom as the lead role. She didn’t have the most normal high school experience, considering she had to balance between her busy work schedule and going to classes. However, by the time she finished Blossom and graduated from high school, she was already accepted to both Harvard and Yale. However, wanting to stay close to her family she decided to attend UCLA.
Johnny Galecki as Leonard Hofstadter
Johnny Galecki was introduced in the first season as Sheldon’s roommate. Although Sheldon is often a bit too much for Leonard to handle, he cares for him very much and sees him as his best friend. Leonard, similar to his friends, is highly intelligent and received his doctorate from Princeton at the age of 24. He fell for the pretty blonde next door, Penny, and the two are now married in one of the most adorable on-screen relationships ever.
Johnny Galecki- in high school
Before he was making millions on TV, he grew up with his two siblings and parents in Oak Park, Illinois. His mother worked as a mortgage consultant and his father was in the U.S. Air Force. Johnny got his first acting role at the age of 12, in the CBS miniseries Murder Ordained. His career took off shortly after and he dropped out of school at the age of 14.
Simon Helberg as Howard Wolowitz
Simon Helberg plays aerospace engineer and former astronaut Howard Wolowitz. Howard grew up with an overbearing mother who often treated him like a child despite his scientific achievements. He was introduced to his current wife, the sassy yet adorable Bernadette in the third season while she was working as a waitress with Penny at The Cheesecake Factory. Howard and Bernadette have a baby girl together named Hallie.
Simon Helberg- in high school
Simon Helberg hasn’t changed all that much since his school days, he even still has the same haircut! Simon grew up in LA with an actor as a father and a casting director for a mother. It was no doubt with genes like his that he would go on to do big things! He went to Crossroads School in Santa Monica, California with his friend and fellow actor Jason Ritter. The two later went on to be roommates at NYU.
Kunal Nayyar as Rajesh Koothrappali
Kunal plays Rajesh Koothrappali, or ‘Raj’ on the show. He is an astrophysicist and Howard’s best friend. He was portrayed as having a severe social anxiety that prevented him from being able to talk to women. Luckily for him, he overcame his fear and has dated several women since then, maybe a bit too many in fact.. he got trapped in the middle of a love triangle between two different women in the 9th season.
Kunal Nayyar- in high school
Does anyone in the cast of Big Bang actually age? Although Kunal was born in London, he spent most of his childhood in new Delhi, India where he studied at St. Columba School. He was on the school’s badminton team, and didn’t find his passion for acting until he moved to the US to attend University of Portland. There, he started taking acting classes in between his Finance courses. He appeared in almost every school play.
Laurie Metcalf as Mary Cooper
Sheldon’s mommy dearest, Mary Cooper, is played by none other than the Emmy and Tony Award winning actress Laurie Metcalf. As a devout born-again Christian, Mary couldn’t possibly be more opposite from her son, who believes in science and not God. However, she proves to be a devoted and loving mother and is one of the only people who truly gets him and can make him see any sense.
Laurie Metcalf- in high school
Laurie Metcalf grew up in Edwardsville, Illinois and attended Edwardsville High School. She had an interest in performing at a young age, but her incredibly shy personality made it difficult for her. Eventually, she forced herself to overcome her fears and auditioned for her first play in high school. She was hooked right away and auditioned for every production that came after. Growing up, she never thought that her passion would amount to anything… well, she was obviously wrong!
Kate Micucci as Lucy
Kate Micucci plays Raj’s socially awkward and adorable former girlfriend Lucy. He met her at a single’s party that took place in the gang’s favorite comic book store. Lucy is portrayed as a very anxious woman who doesn’t do well in social scenarios. Raj, who can relate, falls for her and the two start dating until she eventually breaks his heart via text message. She claimed it was due to the fact that he pushed her too far, and she couldn’t handle hanging out with his friends.
Kate Micucci- in high school
The lovely Kate Micucci grew up in Nazareth, Pennsylvania and attended Nazareth Area High School. Throughout high school, she spent most of her time either working at the concession stand in the local Regal Cinemas or taking classical piano lessons, which were taught by her own mother. By the time she graduated from high school, she decided to say goodbye to her small town in order to study Studio Art in LA’s Loyola Marymount University.
Christine Baranski as Dr. Hofstadter
The incredibly talented Christine Baranski portrays Leonard’s mommy, Dr. Beverly Hofstadter on the show. With Beverly being a neuroscientist and award-winning psychiatrist, it is pretty obvious where Leonard got his smarts from. Although the two stay in touch for frequent visits and video chat calls, Beverly is not portrayed as being mother of the year. She is generally cold, bitter and seemingly emotionless- so much so that she even criticizes Leonard when he shows emotion.
Christine Baranski- in high school
Christine was born in Buffalo, New York to two Polish parents. Her father edited Polish newspapers and her grandparents were both actors in the Polish theater. She attended Villa Maria Academy in her hometown, where she was class president. It was in high school that she discovered she had a passion and talent for acting, just like her grandparents. As soon as she graduated high school, she got accepted to Julliard, where she studied theatre.
Eliza Dushku as Angela Page
The stunning Eliza Dushku had a guest appearance on the series as FBI agent Angela Page. She visits the apartment in order to interview Howard’s friends for a job on the Equipped Surveillance Satellite Team. Leonard flirts with her, Raj tries to convince her he is legal and Sheldon tells her about the time Howard crashed the Mars Rover. Safe to say, Howard failed the clearance and didn’t get the job.
Eliza Dushku- in high school
See, even celebrities had to suffer from forehead acne as a teenager! Eliza grew up in Watertown, Massachusetts right outside of Boston. Her father was a Boston school teacher and her mother worked as a college professor. While she was attending Watertown High School, she was also pursuing a professional career in acting. She ended up landing a lead role as Alice Bloom in the film That Night when she was only 10-years-old. Eliza managed to graduate from high school while working as an actress. She intended on studying at Suffolk University the following year, but got casted as Faith in Buffy the Vampire Slayer instead.
Margo Harshman as Alex Jensen
Margo Harshman plays Sheldon’s assistant. Although she is a Caltech physics doctoral student, and well-equipped for the job, Sheldon insists on giving her menial tasks and doesn’t allow her to actually assist him with his research. At one point she fell for Leonard, who didn’t seem to notice. Penny obviously noticed her boyfriend’s new admirer, and was not impressed. By the time Margo finally asked Leonard out, he turns her down due to his loyalty to Penny.
Margo Harshman- in high school
Margo Harshman was raised in San Diego with four siblings. She and her family moved to Orange County, California where she studied at Foothill High School. She started competing in beauty pageants at a young age, and also took lessons in dance and piano. She started acting when she was only 8, and spent most of her teenage years balancing her school work and acting jobs. During her freshman year of High School, she got casted in Disney’s Even Stevens as Tawny Dean, who she played for three years.
Sara Rue as Stephanie Barnett
Sara Rue played Stephanie Barnett in a few episodes in the second season. Stephanie is a doctor and surgical resident who first got the attention of Howard, who tried to impress her by letting her drive a Mars Rover. She fell for Leonard instead, and they get so close that she basically moves in with him. The relationship ends after Leonard breaks up with her via text message.
Sara Rue- in high school
The talented Sara Rue grew up in New York City with an actress as a mother and a stage manager as a father. Her parents were incredibly active in Broadway, and it was only natural that their daughter would want to follow in their footsteps. She was already acting professionally by the age of nine, when she appeared as Kevin Spacey’s daughter in the film Rocket Gibraltar. Her career took off shortly after that and she didn’t have the most typical teenage life.
Sara Gilbert as Leslie Winkle
Sara Gilbert reunited with her former Roseanne costar Johnny Galecki for several episodes as Leslie Winkle, Leonard’s work partner. Leslie is pretty much the exact female version of Leonard, and the gang even notices that they wear the same hoodie and have the same black framed glasses. Leonard and Leslie date for a brief period of time, until she moves on to having a friends-with-benefits relationship with Howard.
Sara Gilbert- in high school
If you can’t already tell by this picture, Sara Gilbert pretty much had a way cooler teenage life than any of us. The Santa Monica native met and befriended Leonardo DiCaprio while attending some of the same auditions. Sara landed the longtime role as Darlene on Roseanne when she was only 13-years-old. As a teen, she dated ’90s heartthrobs Toby Maguire and her Roseanne/Big Bang Theory costar, Johnny Galecki. She somehow managed to do all this while studying at Yale University.
Alice Amter as Mrs. Kothrappali
Alice Amter portrayed the role of Raj’s lovely mother with no first name, Mrs. Kothrappali. She is typically seen via video chat asking Raj why he isn’t married to a nice Indian girl and why she doesn’t have grandchildren yet. She considers Howard the closest thing she has to a daughter-in-law, and insists on calling him “that Jewish boy.” She and Raj’s Dad, V.M. Koothrappali aren’t the best example of a perfect marriage, considering they got a divorce in 2015.
Alice Amter- in high school
Can we all agree that Raj’s mom is looking fierce in this photo?! Alice Amter was born in Birmingham, England but moved around a lot as a child and spent some time in a foster home until her single mother came to take care of her. She studied at Milverton Junior and High School and later on studied at Wolverhampton University. After spending some time in France, Germany and Japan teaching English, she decided to move to LA in the late ’90s in order to pursue her true passion, acting.
John Ross Bowie as Barry Kripke
John Ross Bowie portrays the recurring character, Barry Kripke. Barry is a Caltech plasma physicist turned string theorist…basically he is a genius like Sheldon and the rest of the gang. He may be blessed with intelligence, but he definitely knows how to rub people the wrong way which can cause him to be quite an unlikeable colleague. Not to mention, he sounds like Elmer Fudd from Looney Tunes due to his case of rhotacism.
John Ross Bowie- in high school
Is young John Ross Bowie not the cutest thing you have seen all day? Just look at those glasses! John was born and raised in the big apple and attended high school in New York City’s Baynard Rustin High School for the Humanities. After he graduated in 1989, he enrolled in Ithaca College with a BA in English and Education. Despite his degree, he always knew that performing was his true gift. He was later part of a sketch comedy troupe with comedians Rob Corddry, Brian Huskey and Seth Morris. He was even a member of a pop-punk band called Egghead at one point.
Courtney Henggeler as Missy Cooper
Courtney Henggeler appeared on TBBT as Sheldon’s fraternal twin sister, Missy Cooper. She is charming, optimistic, outgoing, pretty much the the complete opposite of her brother. When she visits Sheldon in the first season, Leonard, Howard and Raj all fall for her and compete for her attention. Although her and her brother are incredibly different, she still loves him very much and is proud of everything he has achieved with his career.
Courtney Henggeler- in high school
Throughout her childhood and teens, Courtney Henggeler was always known as being theatrical, and had a true passion for performing. She grew up in New Jersey, where she had her first ever audition for her high school’s production of Carousel. She continued to appear in each school production that followed, and she eventually moved to Los Angeles to take acting lessons and to pursue her career as an actress.
Riki Lindhome as Ramona Nowitzki
Riki Lindhome played Ramona Nowitzki, Caltech employee and Sheldon’s number one fan. After she meets her idol Sheldon, she sets up a dinner date at his apartment. The gang all find her a bit stalker-ish, but Sheldon just sees it as a free dinner. They continue to hang out until she asks Sheldon to share credit with him on a theorem, which causes him to immediately kick her out.
Riki Lindhome- in high school
Riki Lindhome was born in Pennsylvania, but grew up in Portville, New York, where she also attended high school. She knew from a young age that she loved to perform and make people laugh. After high school she decided to attend Syracuse University, where she took acting courses and was part of the campus’ sketch comedy group called Syracuse Live. Once she finished her degree in 2000, she embarked on a career in acting.
Wil Wheaton as himself
Former Trekkie star Wil Wheaton has been playing himself, well a much darker version of himself, on The Big Bang Theory since the show’s very first season. In the earlier seasons he tended to get on the wrong side of Sheldon, quite a lot actually. The two did not get along until the 5th season, when Sheldon and Wil finally made amends and became close friends, well as close as you can get with Sheldon.
Wil Wheaton- in high school
Wil Wheaton did not have the most typical childhood. The Burbank, California native started going to auditions as a child, and made his first breakthrough role as Rob Reiner in 1986’s Stand by Me, when he was only 14-years-old. The following year, he made his debut as Wesley Crusher in Star Trek: The Next Generation, which he did for four seasons. During that time, he still managed to graduate from high from LA’s Crescenta Valley High School.
Alessandra Torresani as Claire
Alessandra Torresani portrayed the role of Claire, Raj’s former love interest. She is a screenwriter and bartender who met Raj while he was with Howard at the comic book store. She asked Raj to help work with her on her script for a kid’s sci-fi film. Raj eventually falls for her even though Claire isn’t interested. Later on, she changes her mind and Raj ends up leaving Emily in order to pursue a relationship with Claire.
Alessandra Torresani- in high school
Alessandra Torresani grew up in Palo Alto, California. She was raised by two tech parents who ran their own companies. She decided to go a completely different path than her parents, and she started taking acting, dancing and singing classes when she was only two-years-old. She didn’t have the most usual childhood, and by the time she was a young teen in high school, she was already appearing in series like Popular and Even Stevens.
Valerie Azlynn as Alicia
Valerie Azlynn played Alicia, the aspiring actress who moved into the apartment above Leonard, Penny and Sheldon. She first met Leonard and Sheldon in the building’s lobby, and not before long the whole gang start to fall for her. The guys start to do several favors for their new neighbor, and Penny gets a bit annoyed and jealous. The two ladies get in a fight, which results in Penny getting a black eye. After Penny’s friends see what happened, they finally decide to cut ties with Alicia.
Valerie Azlynn- in high school
Valerie Azlynn grew up in Connecticut, and attended Waterford High School. When she was only 13, she had to undergo open-heart surgery. Following the surgery, she continued with her high school education and moved to New York City as soon as she graduated. She studied acting at the New York Conservatory for Dramatic Arts for two years, and her career in television started to take off not too long after that.
Laura Spencer as Emily Sweeney
The beautiful ginger, Laura Spencer, plays Raj’s former girlfriend Emily Sweeney. Emily is a dermatologist who first met Raj on his dating site in the seventh season. Raj ends up dating her at the same time as Lucy, and Emily is okay with it… unlike Lucy. Raj admired Emily for her odd sense of humor and her passion for scary movies. The two end up having a pretty steady relationship until Raj ends it in order to pursue Claire. Poor Emily.
Laura Spencer- in high school
Laura Spencer was born and raised in Oklahoma City, Oklahoma, where she also went to high school and college. As a teenager, she had already developed a passion for performing and decided to take courses in acting during her studies at the University of Oklahoma. It was there that she met a casting director who assisted her with moving to LA and pursuing a career in television. Look at how cute she looked as a ’90s teen!
Michael Trucco as David Underhill
Michael Trucco made a guest appearance during the second season. He played the role of David Underhill, a highly successful physicist who Leonard was extremely excited to be working with. Penny falls for him right away due to his “bad boy” style, which is the opposite of most physicists she knows. The two have a fling until she finds out that he is actually a married man.
Michael Trucco- in high school
The California native grew up in San Mateo. He went to school at Junipero Serra High School, and as we can see he was most likely the coolest kid in school and probably the crush of every ’90s girl. After he graduated from high school, he was planning on becoming a police officer, just like his father. However, once he got to college, he decided to take a theatre course, and the rest is history!
Steven Yeun as Sebastian
Before Steven Yeun hit fame for portraying Glenn in The Walking Dead, he had a brief role on The Big Bang Theory. Although he didn’t have many lines, the lines he did have were pretty epic. You might remember Sebastian as the guy who is seen in a flashback when Leonard is telling the story of how he met Sheldon to Penny. Leonard saw Sebastian leaving the elevator with his remaining belongings while he was moving out. Leonard asked where Sheldon’s apartment is and Sebastian just tells him to “Run fast, run far.”
Steven Yeun- in high school
Now you see why we included Steven on this list?! Look at how adorably geeky he looks in his yearbook photo! Pretty sure we love him even more now. Steven Yeun was born in Seoul, South Korea before moving to Canada and then later to Michigan, where he attended Troy High School. He later chose to study psychology at Kalamazoo College, where he developed a passion for comedic acting after watching the college’s improv group, Monkapult.
Summer Glau as herself
The gorgeous sci-fi star Summer Glau popped by the set of The Big Bang Theory during the show’s second season. The gang ran into her on the train, and they all fought over who would get the chance to approach her and try to talk to her. Howard thinks of a clever line to say, and comes up with, “it’s hot in here, it must be summer.” Raj gets to the actress before and steals his line, making a good impression.
Summer Glau- in high school
Guessing by this picture, Summer was anything but an awkward teenager. The Texas native had a passion for ballet before acting and received a scholarship to a ballet company when she was in the 3rd grade. From grades 3 to 12 she ended up getting homeschooled in between her ballet training. In 2002, she suffered a broken toe which ended her dancing career, and she decided to move to Los Angeles to pursue a career in acting instead.
Nathan Fillion as himself
The talented Nathan Fillion made a guest appearance during the 8th season of The Big Bang Theory. He played himself in an episode where fans Raj and Leonard spot him at a restaurant. Raj suggests they ask him to do a celebrity signing event at Stuart’s new shop, but Leonard is reluctant because if he is mean in real life it would mean ruining Firefly for him. They get up the courage to approach the actor, but he insists that he is not really Nathan Fillion.
Nathan Fillion- in high school
Could anyone sport a mullet better? Nathan Fillion was born and raised in Edmonton’s Mill Woods in Canada, where he studied at Holy Trinity Catholic High School. He developed a passion for performing as a teenager, and after he graduated from Concordia University College of Alberta he made the big move to New York City to pursue his acting career. While he was there he did mostly theatre productions, until he landed his first big role as Joey Buchanan in One Life to Live.
Christopher Lloyd as Theodore
Of course, we know him better as Doc from the Back to the Future movies, but Christopher Lloyd graced the set of The Big Bang Theory in the 10th season. Theodore is an old homeless man that Sheldon rents his old bedroom to so that he can get revenge on Leonard. Theodore ends up being the one to patch up the two fighting friends, by making them realize that they are only arguing because they care about each other.
Christopher Lloyd- in high school
The great Christopher Lloyd grew up in Stamford, Connecticut where he also attended high school. He formed a love for acting when he was 14-years-old, after working as an apprentice at a summer stock theatre. By the time he graduated from high school, he already knew that he wanted to pursue acting professionally, so he moved to New York City and enrolled in acting classes at New York City’s Neighborhood Playhouse School of the Theatre, with the renowned acting coach Sanford Meisner.
Melissa Rauch as Bernadette Wolowitz
The adorable, petite yet intimidating blonde Bernadette Wolowitz, is played by the talented Melissa Rauch. Bernadette is a microbiologist who was introduced in the third season as a student and co-worker of Penny’s at The Cheesecake Factory. She was set up with Howard by Penny, and she was not impressed until she found out they both have overbearing mothers. The two continue to date until the 4th season where they get married, and later on welcome a baby girl named Hallie.
Melissa Rauch- in high school
Before she was Bernadette, she was just an average, shoulder pad and scrunchy wearing teenage girl from a small New Jersey town. She found her passion for acting while she was a student at Marlboro High School. She started taking acting classes and appeared in almost every school production until she eventually moved to NYC where she studied at Marymount Manhattan College while working as a stand-up comedian.
Kaley Cuoco as Penny Hofstadter
Kaley Cuoco plays the beautiful former neighbor and current wife of Leonard. She first appeared on the show as an aspiring actress and waitress, and grabbed Leonard’s attention right away. Although he didn’t think he was good enough for her at first, the two end up having an on-again-off-again relationship until finally getting married in Vegas in the 9th season. Penny has since quit working as an actress and waitress and took a job working as a pharmaceutical rep at Bernadette’s company.
Kaley Cuoco- in high school
Before she was one of the highest paid actors on television, Kaley Cuoco was actually a tennis player. She grew up in Camarillo, California where she started the sport when she was only 3-years-old, by the time she was 16 she was a regionally ranked player. Like many young actors, Kaley was home schooled while on set. She received her high school diploma when she was only 16, right before her debut as Bridget Hennessy on the series 8 Simple Rules.