KANSAS CITY, Mo -- You could call it the Case of the Missing Diamond Earrings.
Except in this mystery, we know where the earrings disappeared to.
A pair worn by Diana, Princess of Wales, at her wedding nearly 30 years ago arrived in late February at Kansas City, Mo.'s, Union Station along with everything else in the "Diana: A Celebration" exhibit.
But the 40,600 visitors who have seen the show so far haven't seen the earrings.
They were sent back to England before the show opened March 4.
Watch your TV closely on Friday, the day Prince William and Kate Middleton wed. You might catch a glimpse of the earrings sparkling on the ears of Lady Sarah McCorquodale, Diana's oldest sister.
She and Diana's two other siblings -- Lady Jane Fellowes and Charles Spencer -- will be seated across the aisle from the royal family, behind Kate Middleton's parents, in Westminster Abbey.
British royal watchers hailed Lady Sarah's wedding-day fashion choice because it will represent a little part of Diana at her son's wedding.
In addition to William, of course.
The earrings once belonged to the siblings' mother, Frances Shand Kydd, who died in 2004. Each earring has a pear-shaped diamond surrounded by nearly 50 smaller diamonds.
Diana's mother lent them to her for her first public appearance after she and Charles announced their engagement.
On her wedding day in 1981, they were the "something borrowed" in Diana's wedding attire.
The best glimpse of the earrings came when Diana and Charles kissed on the Buckingham Palace balcony after the ceremony.
"They physically were here in Kansas City, but they never got unpacked and put on display," said Tony Cook, a Union Station spokesman.
Cook doesn't expect the earrings to return to the exhibit, which wraps up June 12.
And if a certain queen of daytime talk had her way, exhibit goers on Friday would have missed seeing Diana's famous wedding gown, too.
To celebrate the wedding, Union Station is hosting the biggest watch party in town and offering reduced rates to the exhibit that day.
The gown is, without question, the exhibit showstopper, the reason national media are coming Friday to Kansas City.
Late last week Cook received a request from "The Oprah Winfrey Show."
Oprah wants Diana's wedding dress ... in her studio... in Chicago ... on Friday, the day of the wedding!
Oprah would arrange to transport the dress back and forth and would help promote the exhibit there in Kansas City, a show representative told Cook.
"I said, 'I'm sorry, we cannot not have the wedding dress on display,"' Cook said. "It's such a big thing. There's no way I cannot have the dress here.
"I said, 'She's welcome to come to Kansas City.'
"So yes, I had to tell Oprah no."
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