It's literally the thing of nightmares. We use elevators every day and you almost never hear about accidents or disasters. Even so, dreams of being in a falling elevator are so common they have their own distinction on many dream analysis sites.

With that said, you run the risk of losing sleep if you continue reading.

You've probably heard of the John Hancock Building in Chicago. It changed its name to 875 North Michigan Avenue, but it's still one of the most iconic towers in the world. With two antennae sticking up like ears, it's an easy way to recognize Chicago.

At 100 floors, it's the second-tallest building in Chicago and commands an unmatched view of the city and surrounding areas. The observation deck is on the 95th floor and is a common tourist stop when people from around the world come to visit.

A group of six strangers were coming down from the deck and opted to take the express elevator down. They got more than they bargained for.

The tower is, ironically, known for it's fast elevators. UrbanMatter, a North American tourist website, lists it as having the fastest elevators in North America. Even so, as the elevator began to zoom faster and faster towards the ground, the people inside knew something was wrong.

"At the beginning I believed we were going to die," Jaime Montemayor told the press. "We were going down and I heard a noise - clack clack clack clack."

His wife described dust starting to fly into the elevator car as they plummeted to the ground. They came to an abrupt stop, thankfully leaving no one injured. It wasn't until they were rescued three hours later they found out they had fallen 84-floors down to the 11th floor.

Since they had taken an express elevator there was no way to reach the now stranded car. Firefighters had to break in through the shaft wall to open the door. CBS News reported that an elevator-to-elevator rescue was impossible because the car was too unstable.

While still under investigation, it appears that the accident was caused by a snapped hoist rope. Modern elevators have several ropes, the remaining cables are what stopped the car before it met a tragic crash at the bottom of the shaft.

According to reports the elevator was last inspected in July. The Center for Disease Control says elevator and escalator accidents kill about 30 Americans every year, mostly repair workers.