When it comes to The Big Bang Theory, the viewers have been gifted with some memorable holiday episodes. There was the Christmas episode where Sheldon received Leonard Nimoy's napkin. There was the Thanksgiving episode where Penny discovered she was married to Zack. However, the ones that have proven most popular among fans have to be the Halloween installments.

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It's not just because of the hilarious and dynamic storylines but also because fans enjoy seeing what costumes the gang comes up with. For those still on the fence about their next Halloween costume, maybe it's time to rewatch some holiday episodes of The Big Bang Theory for some inspiration.

Indiana Jones

Indiana Jones in The Big Bang Theory Raj costume

While fans had seen Raj in numerous outfits over the years, many would agree that one of their all-time favorites had to be the Indiana Jones outfit. In, "The Holographic Excitation," fans were highly impressed with Raj's costume as he had all the architect's iconic details.

From the brown fedora to the leather jacket, this outfit suited Raj well. It would also work great as a Halloween costume and is quite simple to create, too. Many stores still sell faux-leather jackets and the hats can be easily found online. All you need is a khaki shirt and you're good to go.

Willy Wonka

Willy Wonka costume Stuart The Big Bang Theory

Another show-stopping costume the fans thoroughly enjoyed was Stuart's Willy Wonka costume. Also seen in "The Holographic Excitation," Stuart's costume proved to be a hit with his friends as he transformed himself into the candy man from the 1971 film.

If someone attempted to replicate this look then they needed to attain several things. Firstly, one would have to get the purple coat since this was a distinctive part of Willy Wonka's look. While the top hat is a vital element to the outfit, it could be any color. A person would also need to get a large bowtie to complete the assemble.

Disney Princesses

In the season 6 episode "The Contractual Obligation Implementation," the viewers also discovered the girls didn't mind dressing up occasionally when fans saw them transform into several Disney Princesses. While viewers will agree that the costume and make-up department did a good job in transforming the women into Aurora, Cinderella, and Snow White, a lot have wondered if they're worth it as a costume.

If some are still hesitant, here are just a couple of reasons. For one, the dresses seem to be very comfortable and easy to move around in. Two, it doesn't require someone to put much effort into their makeup or hair. Three, the dresses are long enough for someone to put on a pair of tights and conceal them if the weather gets colder. It's a win all around.

Harry Potter And The Hogwarts Students

Mayim Bilaik and Jim Parsons

While this may not be as creative or unique as the other costumes, a lot of people may feel comfortable going as a character from Harry Potter. On numerous occasions, the viewers have seen the gang don their Hogwarts robes and visit the Universal Hollywood theme park. Fans were also ecstatic to learn that Amy was a Hufflepuff while Sheldon was a Gryffindor ("The Birthday Synchronicity").

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If becoming a Hogwarts student is something that appeals then there are a few things one needs to do. One could rent a costume from the store and become a main character. The other option is taking a Sorting Hat quiz, buying one's house robe and scarf, and then purchasing a wand. Then one will have a costume that can be used in the future.

Dressing As The Characters

Sheldon Amy Howard in The Big Bang Theory

One of the more obvious costumes choices would be to dress up as the characters themselves. As fans remember, "The Imitation Perturbation" also saw tensions within the gang rise when they decided to dress up in each other's clothes. First, it started with Howard copying Sheldon, which then escalated to Sheldon and Amy dressing up as Howard and Bernadette.

This is probably one of the easiest of costumes to replicate as it just requires one to copy the characters' styles. If someone wants to go as Sheldon, make sure they have a Flash t-shirt. All a Bernadette costume needs is a pink cardigan and flowery dress. For Howard, someone just needs a plaid shirt and novelty belt buckle. It's as easy as that.

Mary Poppins And Bert

Bernadette and Howard as Mary Poppins and Bert.

While a lot of people like to experiment with their costumes creatively and independently, there are others who prefer the "couple's costume." This seemed to be the case with Howard and Bernadette — who always seemed to come up with a winning combination.

A prime example of this was in "The Imitation Perturbation," where Bernadette and Howard's interpretation of Mary Poppins and Bert proved a hit with everyone. Especially Bernadette's — from the red coat to the flowered black hat, fans knew exactly who she was. One would be sure to steal the show if they copied this look.

Dr. Emmett Brown And Clara Clayton

Sheldon and Amy as Doc and Clara in TBBT

Another couple's costume seen on the show was Dr. Emmett Brown and Clara Clayton. Also in "The Imitation Perturbation," the viewers discovered that Sheldon was a big fan of Robert Zemeckis' Back To The Future franchise as he asked Amy to dress up as Clara Clayton so he could be Emmett Brown.

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Although a person should forgo the corset since they are highly uncomfortable, many fans were amazed by Amy's transformation — especially as the costume department managed to create Clara's iconic look with the lavender dress and straw hat.

The Justice League

Big Bang Theory cast as Justice League Costume

On several occasions, fans have seen the writers make several nods to the DC Comics. However, the best reference had to be the gang's costume in "The Justice League Recombination."  As fans know, the boys, plus Penny and Zack, all decided to enter a New Year's Eve competition dressed as the Justice League. Fans thoroughly enjoyed seeing the outcome as the characters looked very similar to their comic book counterparts.

This has inspired several fans decided to go with this idea for Halloween. It's not a complex costume either — all someone has to do is go to the store or buy it online. In fact, one may have more trouble trying to find six people to agree to the ensemble than acquiring the costumes...

The Smurfs

The Smurfs TBBT Howard and Bernadette

Another underrated costume of Bernadette and Howard's had to be when they dressed up as Smurfs. Not only did "The Holographic Excitation" provided another great costume idea but Howard and Bernadette proved pure dedication when they spent three hours painting themselves blue.

While one might not want to go this far for one night, it can still be done. Someone could always substitute a blue shirt in and just pain their face instead. While the more accurate colors for a Smurf are white, red, and blue, anything close to the colors works just as well too. It's just essential that one has the hat.

Inspector Gadget

Leonard as Inspector Gadget in TBBT

One of the best and most creative costumes that should earn anyone the top prize is Leonard's Inspector Gadget. First seen in "The Imitation Perturbation," fans were amazed to see the physicist's costume as it was a direct carbon copy of the animated series.

This is a fairly easy costume to pull off. All someone needs is a gray raincoat, a trilby hat, some blue pants, and gloves. One could even go the extra mile and include some of his gadgets (e.g. the copter, springs). This will also be a hit with those who love '80s nostalgia.

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