Mayim Bialik has explained why Jim Parsons was so good at playing Sheldon on The Big Bang Theory. As one of the original characters on the show, Parsons, alongside Johnny Galecki, were the only two actors who stuck around after the hit sitcom's original pilot was re-worked. Bialik played Amy Fowler, a neurologist who meets Parsons' Sheldon Cooper through Raj and Howard, and the two eventually marry.

It has been almost three years since The Big Bang Theory wrapped up, despite still being popular. Its home network, CBS, wanted to continue the series and had plans to renew it for season 13 and 14. However, Parsons wanted to exit The Big Bang Theory after season 12, believing it was time to move on from the character of Sheldon and his beloved friends. Deciding not to push through with an incomplete cast, Parsons' co-stars ultimately agreed to end the series together after The Big Bang Theory season 12. However, thanks to re-runs and availability on various streaming platforms, the show's popularity endures, and Sheldon remains a fan-favorite.

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In her recent guest appearance on THR's Top Five podcast, Bialik (who is a real-life neuroscientist as well as being an actor) opened up about why Parsons was so good playing the character, despite not being a real scientist like her. The actress simply chalked it up to his co-star being a great actor, especially given how tricky it was memorizing his often complicated, science-based lines. Read his full comment below:

"So yeah, you don’t need to be obviously a neuroscientist to play one on television. It helps more in terms of memorization but Jim Parsons, he clearly is not a brilliant physicist and is a phenomenal actor.”

big bang theory Hofstadters wedding gift to sheldon amy

While The Big Bang Theory was technically an ensemble show, its true lead has always been Sheldon. Over the years, that became clearer as the sitcom gradually shifted its storytelling to focus on both the character's personal and professional life. In fact, much of The Big Bang Theory's final season 12 was about him and his bid to win the Nobel Prize in Physics. CBS even staged a one-time crossover with TBBT prequel series Young Sheldon, which saw George (Lance Barber) and Georgie (Montana Jordan) appear on the nerd-centric sitcom. However, while his character proved popular, the decision to center the show's narrative on Sheldon was divisive, as many viewers felt it made the rest of The Big Bang Theory cast supporting characters instead of major players.

The Big Bang Theory may be over, but fans can still enjoy Parsons' Sheldon storyline through Young Sheldon. While Iain Armitage plays the younger version of the character, Parsons provides the narration for every episode. Several actors from the original series have also had voice cameos in the prequel, including Bialik, who reprised her role as Amy to reveal that she and Sheldon now have a son named Leonard Cooper. Ultimately, Parsons and his co-stars' memorable performances on The Big Bang Theory will go down in sitcom history, and it is heartwarming to hear that their work was not only respected and enjoyed by audiences, but by each other as well.

More: Young Sheldon Hints At Penny & Leonard’s Dark Future After Big Bang Theory

Source: THR's Top Five