Jim Halpert is famous on The Office for his inventive pranks on Dwight and his knowing looks to the camera. Star John Krasinski, who played the lovably underachieving Dunder Mifflin sales representative, underwent quite the hairstyle transformation throughout the course of the show. He started off with a shaggy Beatles-esque mop-top before ending with a neater, more stylish look.

What is less commonly known, outside of passionate The Office fans, is that Krasinski actually wore a wig that went largely unnoticed for a decent chunk of Season 3. In a recent interview, The Office hair and makeup artist Kim. M Ferry revealed that Krasinski cut his hair in order to star in the George Clooney-directed film Leatherheads.

Krasinski badly wanted to star in the 1920s football film, but still had to finish his duties on the hit NBC sitcom. Knowing that his haircut would likely not be approved by higher-ups, Krasinski conspired with Ferry to dupe the show's creator Greg Daniels with a wig.

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John Krasinski Leatherheads

Krasinski enlisted the best wig maker in town to make him a wig of human hair. He then secretly put the wig on and went to Daniels' office to convince him to let him star in the film. Daniels adamantly refused, saying he would notice something like that easily. Krasinski then took off the wig and said, "No, I don't think you would." Stunned, Daniels relented and Krasinski was able to take the part. As a result, the final six episodes of Season 3 feature Jim Halpert sporting a secret hairpiece.

Now that the cat's out of the bag, let's investigate if we can pinpoint exactly when the Big Tuna was the Big Wig. (Apologies to Krasinski in advance if his real hair is mistaken for a hairpiece.)

Jim Original Hair The Office

Here we have a Jim Halpert in his natural habitat; the Jim Halpert the world fell in love with, in all his bowl-cut glory.

"Cocktails"

Jim Wig The Office

And here we have the first appearance of the Jim Wig. According to Ferry, the first time Krasinski wore it was in the episode "Cocktails," in which Jim and others attend a party at David Wallace's house. Krasinski shot the whole basketball scene before telling anybody about the wig to prove that it would go unnoticed.

While his hair very well could go unnoticed if you're not paying attention, it's honestly hard to believe Krasinski got this rug past all the folks at NBC. This thing is horrendous. Jim's hair was always messy before but just look at those bangs -- they are the tell-tale sign.

"The Negotiation"

Jim Wig The Office

The next Jim Wig™ appearance is in "The Negotiation," when Roy attacks Jim for kissing Pam in Season 2. Jim and his Wig were saved by Dwight, who subdued Roy with pepper spray. This episode is where the wig stands out at its most obvious. Jim just looks off, the poor guy.

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"Safety Training"

Jim Safety Training The Office

The Tuna's Toupee returns in the classic episode "Safety Gates," when Michael threatens to commit suicide after suffering workplace depression. Jim looking up at the roof gives a better angle of the hairpiece. Again, the bangs look strange -- and maybe it's the lighting, but even the color looks wrong.

"Product Recall"

Jim Dwight Bears Beets Battlestar Galactica

This one hairpiece got to show off its versatility, mimicking Jim's hair as well as Dwight's iconic center part. It's remarkable how many classic moments the Wig got to be a part of. Jim impersonating Dwight is an all-time great Office scene. Bears. Beets. Battlestar Galactica.

"Women's Appreciation"

Jim Face The Office

The wig is a bit harder to detect in "Women's Appreciation," but it did get to be a part of one of Krasinski's patented Jim Looks.

"Beach Games"

Jim Hat The Office

In "Beach Games" Jim dons a hat, effectively hiding the wig. Not only does it makes narrative sense to wear a hat to the beach, but above all, it hides that monstrosity. Well done.

"The Job"

Jim New Haircut The Office

In the Season 3 finale, "The Job", Jim loses the wig and gets a new and improved hairstyle for his job interview with David Wallace. Although Jim got a haircut at the behest of Karen Filippelli, this style is more reflective of John Krasinski's real hair at the time.

Wigged Jim was a revelation, but he will never compare to Natural Jim. Dunder Mifflin's #2 in charge would finally buy a comb and learn how to use styling products, and Krasinski would more or less keep this look for the rest of the show. It was Jim's finest haircut; the man cleans up nice.

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