What do TV executives do when a hit show comes to an end? They create a spin-off, of course! While some have been pretty catastrophic (Joey - Friends), some spin-offs have been so successful they become more popular than the original show (Frasier - Cheers).

With The Big Bang Theory having yet to be renewed past its 10th season despite being the most popular comedy on American TV with the all-important adults 18-49 demographic, it should come as no surprise to learn CBS is looking at the spin-off option.

According to The Hollywood Reporter, a source revealed Big Bang co-creators Chuck Lorre and Bill Prady, along with showrunner Steve Molaro, are working on a new series based on the early life of Jim Parsons' Dr. Sheldon Cooper.

One insider described the project to the publication as ‘Malcolm in the Middle but with a young and potentially teenage version of Sheldon’.

None of the main cast members are thought to be in talks to star while CBC and producers Warner Bros have so far declined to comment on the situation.

Highest Paid Actors Show all 10 1 /10 Highest Paid Actors Highest Paid Actors Actor Jim Parsons Getty Highest Paid Actors Actress Kaley Cuoco Getty Highest Paid Actors Actor Johnny Galecki Reuters Highest Paid Actors Actor Dwayne Johnson Getty Highest Paid Actors Actress Drew Barrymore Getty Highest Paid Actors Actress Emma Stone Getty Highest Paid Actors Actor Jonah Hill Getty Highest Paid Actors Actress Nancy Cartwright Getty Highest Paid Actors Actor Dan Castellaneta Rex Highest Paid Actors Actress Julie Kavner Rex

The report also details how, if Big Bang is to continue, it relies heavily on whether the cast decides to return. Kunal Nayyar spoke about the possibility earlier this year, saying: "To be completely honest…I know people are gonna want to know what happens after season 10. I don’t know what’s going to happen.”