On September 17, 1992, a 14-year-old girl named Misty Copsie went to the Washington State Fair with her best friend.

By 10 p.m., she had vanished into thin air, never to be seen again.

More than 30 years later, no one knows what happened to Misty that night.

From ID and ARC Media, I'm Sarah Kalin, and this is Who Took Misty Copsie?

Every fall since the year 1900,

the Washington State Fair roars to life in Puyallup, Washington.

Puyallup, Washington.

Puyallup sits 10 miles southeast of Tacoma.

In the other direction lie thousands of acres of dense forests and mountains,

with Mount Rainier looming on the horizon, the whole region resting under its watchful eye.

During the fair, the city of about 40,000 swells to many times that size as kids, families, and visitors from all over flocked to the area.

When Diana Smith drops off her 14-year-old daughter, Misty, and Misty's best friend Trina,

at the fair's gates on a Thursday afternoon in September 1992, it feels like any other night.

Misty and Trina are giddy with excitement, two young teenagers getting their first taste of independence.

This is the first time Diana let them go somewhere like this without her or another adult.

Diana told the story in a news segment.

I told her she wasn't going to go because I was a caregiver and I took care of an elderly lady all night long and I wouldn't be able to pick her up.

Her and her friend Trina got on the phone and figured out the bus routes and the times and stuff and she said, Mom, I'm 14, I'm responsible, you know, let me go.

And I said, okay, I said, I'll let you go. You better get that bus home. And I said, last thing I said to her when I dropped her off, I said, Misty, I love you. She goes, I love you, mommy. I said, and if you screw up, I said, you won't do anything like this again. She said, I know, Mom.

Okay, bye.

And she was walking away.

She just looked so little and vulnerable and stuff.

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