This gown, however, carried more than beauty in its seams.

As she entered the screening of The Whales of August, Diana didn’t speak. She didn’t need to. Her dress did the talking.

What most people missed in 1987—but is unmistakable in hindsight—was that Diana’s gown wasn’t just a fashion statement. It was a tribute.

A tribute to another princess who had once walked the same French Riviera shores. A princess whose story, like Diana’s, started in Hollywood, transformed into royalty, and ended far too soon. Grace Kelly—Princess Grace of Monaco—had died five years earlier in a tragic car accident. The same fate that would take Diana’s life just a decade later.

The resemblance was striking. Diana’s flowing dress mirrored the iconic Edith Head gown Grace Kelly wore in Hitchcock’s To Catch a Thief, filmed along the very coast