Why is Late Night Legend David Letterman Filming in Illinois?

David Letterman has reportedly been seen around Illinois this week preparing to film a television special.

Before we get to the details that we know about his visit back to the Midwest, let's look back to when the Late Show with David Letterman visited Chicago.

In 1989, Late Night with David Letterman taped several shows from the Chicago Theater, and featured segments from around the city.

During one segment, Dave is exploring the town with Bozo the Clown.

The two buddies head to the top of what was then the Sears Tower, and visit the Tribune Tower, before they make a wish at the Buckingham fountain.

Here are some other moments from David Letterman in Chicago that will take you back in time.

David Letterman Has a Show on Netflix Called 'My Next Guest'

Since retiring from the Late Show, Letterman has been mainly living in Montana raising his son, and growing a very substantial beard.

But in January 2018, Dave returned for a Netflix series called My Next Guest Needs No Introduction with David Letterman.

Now David Letterman is in Chicago for a taping of the Netflix series, but the guest he's interviewing hasn't been confirmed.

According to an Instagram post from 1iota, a taping of My Next Guest was on December 12 in Chicago.

Screen Magazine reported there would be tapings at The Den Theatre on Milwaukee Ave, in the city’s Wicker Park Neighborhood on December 12 and 13.

While Netflix hasn't officially announced the guest who will appear on the program, there's speculation that it could be Chicago comedian and Emmy Award winner John Mulaney, according to Screen Magazine.