Howard Wolowitz (played by Simon Helberg) was introduced to fans as the only member of the group to still live with his mother (Carol Ann Susi).
Although Mrs. Wolowitz never appeared on screen, fans will remember Howard and his mum screaming at each other through his bedroom door during what seemed like any time Howard wanted a little privacy.
Before Howard married Bernadette (Melissa Rauch) and moved into her apartment in season six, the scientist was regularly seen in his unique room filled with fan memorabilia, posters and action figures.
However, at a closer look fans may notice something unique about the figurines.
Howard’s bedroom shelf features only female action figures with some of the most prominent being Princess Leia, Wonder Woman, and Batgirl.
Looking to the right of his bed, fans will notice tonnes of female action figures dotted around his shelves and side table.
The all-female figures will come as no surprise to fans as Howard is notorious for his cringeworthy attempts to play the womaniser.
Before his partnership with Bernadette, fans often saw Howard get into trouble with Penny for his untimely innuendos.
The room also features various posters of famous women including Marilyn Monroe, Betty Boop and of course the notorious Halle Berry poster on the ceiling.
Fans will remember the classic episode in season two where Sheldon (Jim Parsons) sleeps in Howard’s bed and is unnerved by the pop star floating above him and won’t let Howard sleep.
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The episode saw Sheldon go on about the various Catwomen, eventually noting his favourites in order with Halle Berry coming last.
Howard begged Sheldon to go to sleep, to which he responded: “I’m trying…I’m counting Catwomen.”
The clue comes after eagle-eyed fans noticed something strange about Leonard’s (Johnny Galecki) glasses.
After much speculation, the star finally revealed the glasses are actually fake, revealing the famous specs don’t even have lenses.
Furthermore, the frames were added as a snap decision by Johnny, meaning Leonard could have been a character with perfect vision.
In conversation with Huffington Post the star said: “Oh, man. You’re killing the magic.
“We rehearsed the first episode for about a week and a half, and when we started to shoot, they said, ‘Well, you’re gonna take your glasses off, right?’
“I said, ‘No, I want Leonard to wear glasses.’ They said, ‘Oh, we just thought you were wearing them as Johnny for rehearsal all week.’”
The decisions to pop the lenses were made later on as the star explained he normally has to look up when shooting scenes with co-star Jim, causing the lenses to catch the light.
The Big Bang Theory season 12 is available on CBS and All4.