Wearing a wig on a tv show like Outlander or Game of Thrones doesn't seem weird at all. But wearing a wig on The Office, that's weird. But it's true. For a season of The Office, John Krasinski wore a wig. And he had to demand it. Beg to do it.
On the set of The Office, the wardrobe and make up department didn't have to work that hard. Everyone had to look like normal people who dress business casual. But John Krasinski wanted to wear a wig.
In the newly released Andy Greene book The Office: The Untold Story of the Greatest Sitcom of the 2000s: An Oral History, we learn John Krasinski wore a wig trough the third season of the show. In 2008, he got his big screen break when George Clooney cast him in the mediocre movie "Leatherheads". But the role required him to cut his hair severely to make his hairstyle match the 1920's era.
But Greg Daniels, producer of The Office, was determined to hold John to a clause in everyone's contract that no one can change their hair for continuity purposes. Krazinski begged Daniels saying that he could wear a wig for season three and no one would know. But Daniels insisted he would notice, and fans of The Office would know. It would be ridiculous.
So John went to a person on the set and had them make a wig. He grabbed the wig and walked into Greg's office for one last plea and dropped a wig on his desk. Greg wouldn't budge and insisted he'd know if John was wearing a wig. That's when John pulled another wig off his head... proving he couldn't tell the difference.
And Jim Halpert wore a wig through season 3.