The Big Bang Theory Opening Credits Mistake You Can't Unsee

The galactic, celestial, positively transcendental opening for "The Big Bang Theory" has delighted sitcom fans for years and always managed to unlock their inner nerds. Filled with fast-paced scientific and pop culture references all set to a legendary theme song created by Barenaked Ladies, its bouncy, cheerful braininess helps add to the series' iconic staying power.

But did you know a tiny clerical error buried in those credits makes those opening titles one of the biggest onscreen mistakes in "The Big Bang Theory"? Keep your eyes peeled during the first few seconds of the sequence, where a timeline is created and tracks the billions of years between the Big Bang and the adventures of Sheldon Cooper (Jim Parsons) and his friends. Two seconds in, 92,000 BC is followed by 91,000 9C. Oops! There's a detail that only hardcore fans of the show might know.

Interestingly, no one at CBS or in Chuck Lorre's production offices ever managed to catch the mistake during the show's 12-season run, not even after the series' opening was edited to include new, central characters like Amy Farrah Fowler (Mayim Bialik). But interestingly enough, that's not the only mistake that pops up in those credits. 

Keep watching those titles and you'll notice another typo in that text crawl — though you'll have to slow down the playback speed of your browser or TV when you look for it.

Focus on that timeline and you'll notice that between 1200 BC and 1000 BC, a legend reading 100100 BC instead of 1100 BC passes by. Unless Sheldon and company are traveling beyond pre-history into the very far-flung future and then traveling back to confront the pre-medieval universe, that's another notable error to be dealt with.

Of course, the science put forth on "The Big Bang Theory" isn't always crystal clear and true to life, though it does get several things right. So, perhaps it's fitting that even the credits have a couple of inaccuracies. That's what makes the lovable sitcom so great — it's just as flawed as the characters that populate it, and just as entertaining.

Want to read more about the beloved sitcom? Check out our ranking of every season of "The Big Bang Theory."