The first sign of trouble was when John and Elizabeth Calvert of Hilton Head Island, S.C., failed to show up at their offices on March 4. Popular in the wealthy resort, the Calverts are also known to almost compulsively keep in touch with their employees at Sea Pines Resorts, where they own 125 rental properties and a marina and where they live part-time on a 45-ft. yacht. "We know when they eat, sleep, drink," says dockhand Abbie Adams. But as the day wore on, messages to John, 46, and Liz, 45, on their phones and BlackBerrys went unanswered. Most troubling, perhaps, was that T.C., the couple's treasured cat, was found roaming the yacht unattended. "Liz is an animal lover," says Tony Gibus, who manages the Calverts' social boating club. "She'd never leave the cat."

The Calverts' disappearance stunned high-end, low-crime Hilton Head, and in the days after they went missing, the mystery has only deepened. Investigators—including the FBI—soon began combing the island, interviewing friends and associates. Divers scoured the harbor floor and came up empty. On March 7 police located the Calverts' Mercedes in a hotel lot seven miles from the marina. Then, in a startling development, Dennis Gerwing, a business associate of the Calverts', turned up dead on March 11, an apparent suicide.

From the beginning, authorities focused on two meetings the Calverts had attended with Gerwing shortly before they disappeared. According to sources who know the couple, they believed that someone in the office of their former accountants the Club Group, where Gerwing was chief financial officer, had embezzled more than $100,000. Late last year the Calverts ended their relationship with the Club Group over unpaid bills. On March 2 and again the next day, they met with Gerwing and, according to the sources, planned to discuss the alleged embezzlement. Reached by phone two days before he was found dead, Gerwing told PEOPLE, "It's possible I was the last person who saw them [alive]" and refused to comment further about the business meetings or anything else connected with the case. Club Group CEO Mark King told PEOPLE his company is "actively cooperating with police, who have asked us not to comment."

According to two staffers at the Red Fish restaurant, where Gerwing was a regular, Gerwing came in for dinner on March 7. The staffers say a tear came to his eye when they asked how he was doing. One recalls him saying, "It's been a rough week. The cops think I did it." He then said that police were tailing him and had searched his house and his boat. Those same restaurant employees, however, dismissed the notion that Gerwing could have been involved in anything questionable. "I've known him for years," one says. "He'd give you the shirt off his back. Dennis has helped a lot of people."

Meanwhile, "missing" posters plaster Hilton Head, where the Calverts have been fixtures for more than 15 years. John, a mechanical engineer, proposed to Liz, who also works as a lawyer for a firm in Savannah, while vacationing on the island. "They balance each other," says Mark Leinmiller, an old friend of John's. "He's outgoing. Liz has a quiet wit, but she's not going to be the life of the party." They wed in 1988 and settled into a white brick home in Atlanta's historic Brookhaven district. For a birthday several years ago, John bought Liz flying lessons, and she quickly became a passionate pilot. The Calverts, who have no children, kept coming back to Hilton Head and about five years ago bought their yacht, dubbed Yellow Jacket for the mascot of John's alma mater Georgia Tech.

Four years ago John semi-retired from engineering, and in 2005 the couple took over the Sea Pines businesses. "Calling them my employers doesn't even come close to describing them; we're all one big extended family here," says Laura Tipton, harbor operator at the marina. She calls every couple of days to check on the Calverts' dog Sadie, a black, 45-lb. mix boarding in an Atlanta kennel. She and other staffers also tend to T.C., still on the yacht, where he's most at home, feeding him and administering eye drops for an infection as he waits for Mom and Dad. "I talked to one of their oldest, dearest friends, and he was saying they never wanted to move to Tahiti or someplace like that," Tipton says. "Hilton Head was their dream. They were living their dream."

  • Contributors:
  • Nicole Weisensee Egan/Hilton Head Island,
  • Devan Stuart/Hilton Head Island,
  • Lori Rozsa/Miami,
  • Jeff Truesdell/Atlanta.