Head 40 miles southeast from Savannah, then dive 60 feet down. That's where you'll find Fabien Cousteau this week.
Mr. Cousteau, grandson of legendary undersea explorer Jacques Cousteau, is part of a 10-person crew filming at Gray's Reef National Marine Sanctuary.
They're making a two-hour film for PBS tentatively titled America's Underwater Treasures about the country's 13 marine sanctuaries.
Mr. Cousteau, who like all the crew has never dived at Gray's Reef, knows the sanctuary only by reputation.
"It's quite a treasure trove of animals such as loggerhead turtles, groupers and mantas," he said. "We've got sponges and invertebrates there, too. Geologically it has caverns, caves and underpasses. It's visually stunning. I can't wait."
The marine sanctuaries are the underwater equivalent of the national parks system, Mr. Cousteau said, except that few people can even name the marine sanctuaries, let alone know anything about them.
"Our goal is to make these special places real for viewers everywhere," Mr. Cousteau said.