On a calm beach, a big wave can knock you off your feet—and even act as a thief, as one resort guest recently learned.

Brittania Fisher and her husband were vacationing earlier this month at Miami’s Turnberry Isle Miami, and on their last day there, Brittania was wading in shallow water and picking up shells on the private beach. Suddenly, a big wave surprised her, and knocked her over. "I clenched my left hand because the water was cold, and I knew it would make my fingers shrink," the Dallas native told us. "But my rings were already gone."

She immediately enlisted other people on the beach to help her look, and hotel staffers are still looking—but so far, with no results.

Turnberry's staffers, it should be noted, have recovered lost rings in the past. In 2002, Heather Mills, former wife of Paul McCartney, "lost" one hers when she was staying with the music legend at the resort. "Apparently they had a big row in our Grand Presidential Suite, and in their fight she threw her engagement ring off the balcony," Rachel Pinzur, the resort's public relations director, told NBC Miami. A determined hotel employee found it in the bushes with the help of a flashlight.

The shoreline may pose greater challenges, but Fisher says that she is hopeful that her two rings—both platinum, and soldered together—are heavy enough to have sunk into the sand, rather than be sucked out to sea. (See picture: above.) She recently posted on the resort's Facebook page asking guests to keep looking, and is offering a $2,000 reward for their return.

“There's a dollar amount on the rings, of course, but I can't replace them," Fisher told us. “The engagement ring was what my husband had when he got down on one knee, and he slipped the band on my hand on our wedding day. They're priceless." She's willing to be patient, too. "You always hear stories about people being reunited with items after a long time, so I'll believe in miracles."