How The Big Bang Theory Cast Has Changed Since Their First Season

Take a look back at the stars of the beloved series during their early days on the show

By Jess Cohen May 15, 2019 9:11 PMTags
Jim Parsons, The Big Bang Theory, Then and NowCBS/Warner Bros. Entertainment

We're just one day away from the series finale of The Big Bang Theory.

After 12 seasons, the beloved CBS sitcom—starring Johnny Galecki, Jim Parsons, Kaley Cuoco, Simon Helberg, Kunal Nayyar, Melissa Rauch and Mayim Bialik—will come to an end on Thursday, May 16. As we prepare to say goodbye to the cast of the hit series, we're looking back at photos of the actors during their first season and last seasons.

It's been over a decade since the show premiered, and we've all grown up with the characters on the show. So, as a farewell, let's see how everyone has changed over the years!

See Kaley Cuoco's Reaction to "The Big Bang Theory" Ending

Take a look at the cast of The Big Bang Theory, then and now, below!

Johnny Galecki

CHARACTER: Leonard Hofstadter

Prior to starring in The Big Bang Theory, Galecki actually started his career on CBS in the 1987 miniseries Murder Ordained. 20 years later, Big Bang premiered on the same network, debuting on Sept. 24 of that year. Since the show's premiere, Galecki has become one of the highest-paid actors on television. On a more personal note, Galecki and girlfriend Alaina Meyer will soon welcome their first child together.

Jim Parsons

CHARACTER: Sheldon Cooper

Since the premiere of The Big Bang Theory in 2007, Jim Parsons has captured the hearts of viewers around the world in his portrayal of Sheldon Cooper. For his work, Parsons has received four Emmys and one Golden Globe award. In Oct. 2018, Forbes announced that Parsons was the highest-paid TV actor in the world. This month, the actor celebrates his second wedding anniversary with husband Todd Spiewak.

Kaley Cuoco


Just over two years after the series finale of 8 Simple Rules, Kaley Cuoco landed the role of Penny on The Big Bang Theory. For her work on the show, Cuoco has been nominated for many awards, even taking home a People's Choice Award for Favorite Comedic TV Actress in 2015. The same year that TBBT premiered, Cuoco and co-star Galecki started a relationship, which ended two years later. They still remain close friends.

Later this year, Cuoco will celebrate her first wedding anniversary with husband Karl Cook.

Kunal Nayyar

CHARACTER: Raj Koothrappali

In 2007, Kunal Nayyar rose to fame as astrophysicist Raj Koothrappali. Since that time, Nayyar has become one of the highest-paid actors on TV, alongside Galecki and Parsons. Nayyar has been married to Neha Kapur since 2011.

Simon Helberg

CHARACTER: Howard Wolowitz

Two months before the premiere of The Big Bang Theory, Helberg married actress Jocelyn Towne. In May 2012, the couple welcomed their first child together, a daughter named Adeline. Two years later, the duo welcomed a son, Wilder Towne Helberg.

Melissa Rauch

CHARACTER: Bernadette Rostenkowski

Melissa Rauch joined the cast of The Big Bang Theory in 2009 during the show's third season, playing Bernadette Rostenkowski. Rauch has also appeared on episodes of True Blood and The Office over the years. She's been married to writer Winston Rauch since 2007.

Mayim Bialik

CHARACTER: Amy Farrah Fowler

Mayim Bialik became a household name for her starring role in Blossom, which aired from 1990 to 1995. In 2010, Bialik joined the cast of The Big Bang Theory on the show's season three finale. Since starting on the series, Bialik has earned four Emmy nominations, one Broadcast Film Critics Association Awards win, as well as a win at the Critics Choice Television Awards.

Be sure to watch the series finale of The Big Bang Theory on Thursday, May 16 on CBS.