5 shocking behind-the-scenes secrets from 'The Big Bang Theory'
03 Jul 2025

The Big Bang Theory is an iconic sitcom that has tickled our funny bones across the globe with its combination of science and humor.

While most of us know how the show's characters are quirky and its dialogues are unforgettable, here are some fascinating behind-the-scenes facts you might not be aware of.

These offer an insight into the making of the show.

The original pilot was different
Pilot changes

The original pilot of The Big Bang Theory was poles apart from what we saw later.

While it starred Leonard and Sheldon as the main leads, it had a different female lead, Katie, as opposed to Penny.

After the original pilot failed to impress test audiences, the creators decided to rework it. This resulted in drastic changes in character dynamics and eventually the show's success.

Real science consultants were involved
Science accuracy

To keep The Big Bang Theory scientifically accurate, real-life physicists were involved in the production.

Dr. David Saltzberg, a UCLA professor of physics and astronomy, was instrumental in reviewing scripts for scientific accuracy.

He contributed a lot to keeping authenticity in the scientific conversations depicted on screen.

Kaley Cuoco's injury was written into the show
On-set incident

Kaley Cuoco, who essayed the role of Penny, even suffered an injury while shooting, which led to a temporary adjustment in her character's story arc.

After she broke her leg in an accident out of work, the writers weaved her injury into the show by having Penny fall in the shower.

This way, Cuoco would be able to continue shooting while she healed.

Theme song by Barenaked Ladies
Musical choice

The catchy theme song for The Big Bang Theory was sung by Barenaked Ladies. The band was contacted after they performed at one of creator Chuck Lorre's shows.

They wrote and recorded the theme song especially for this series within a mere two days after getting inspired by Lorre's enthusiasm about their music style.

Jim Parsons never watched Star Trek
Character vs actor

Jim Parsons played Sheldon Cooper as an avid Star Trek fan but had never seen an episode before coming onto The Big Bang Theory.

To think he played an iconic sci-fi nerd on-screen so convincingly over 12 seasons without any prior exposure or interest off-screen towards these genres, it makes his performance all the more impressive to fans around the world.