Where in the World is Patrick McDermott?
It could be the key that unlocks the year-long mystery of Olivia Newton-John's missing boyfriend.
"This could be the smoking gun that breaks this case wide open," revealed John Nazarian, a famed Hollywood private eye who discovered a sun-visor cap said to belong to Patrick McDermott.
"That's the only potential evidence that Mr. McDermott is alive and well and even exists," he added.
"Extra" dispatched Nazarian to Mexico after six witnesses reported spotting Olivia's boyfriend in and around Cabo San Lucas, Mexico.
"We just miss him and love him, and we'd be thrilled if it was true," an emotional Olivia said as she fought back tears on Australia's Nine Network.
While Olivia made her plea, Nazarian was already in Cabo. He came armed with "Extra's" PI cam and was hot on the trail of McDermott. Many people are now speculating that McDermott faked his own disappearance in order to escape a fortune in owed child support payments.
"It's easy to get lost down there if you really want to get lost," Nazarian said of the beachside city, as his search led him along the secular Mexican coastline.
The journey led Nazarian past sparkling beaches and rundown pueblos and into the small town of Pescadaro.
In this small city, McDermott was recognized while patronizing a local watering hole called the Sandbar. Owner Jed Galatro said his staff swears it was McDermott who stopped in, saying they recognized him from "Missing Persons" posters.
Another McDermott sighting happened at Marina's, where owner Marina and son Eduardo told Nazarian that the missing man had dined there with a young mystery blonde.
It was here that Marina says McDermott forgot something -- a hat -- a story corroborated by local journalist Cathy Avillas.
"She said to me, ‘Oh, I remember him. He talked about how much he loved my fish tacos,' and she says he left the hat behind," Marina told Nazarian, who preserved the evidence in a plastic bag and returned with it to "Extra."
"It has enough DNA on it to fill a boat," Nazarian promised.
"Extra" has contacted the U.S. Coast Guard and Olivia and McDermott's family to seek their help with DNA tests that could finally determine if Olivia's missing man is still alive.