"Now, " grunted Ed Dory as he and his fourteen-year-old son, Bill, flipped backward over the side of the Boston whaler. They were scuba diving a mile from shore at Key Largo in John Pennekamp State Park, the famous underwater preserve off the Florida Keys. Looking through the faceplate of his diving mask, Bill could see clearly the teeming life of the coral reef below. There were fish of all shapes and colors, some of which he recognized. Several graceful blue angel fish swam nonchalantly around a large brain coral; tiny striped sergeant majors darted in and out of coral crannies, and a rainbow parrotfish nibbled away at something on the bottom. Bill was roused from his fascination by an insistent metallic rapping sound. Turning, he saw his father a few yards away banging on his air tank with his knife and beckoning to him. Swimming over, Bill watched as his father dug down with the knife, trying to pry loose a square, black object that was half-embedded in the bottom next to a coral outcropping. He had removed the sand all the way around it but something was still holding it down. Bill's father scooped more sand away from underneath it and felt the underside with his hand. He shook his head at Bill and then pointed upward. They kicked toward the surface and, removing their swim fins, climbed into the boat.
Bill, his blond hair plastered around his squarish, freckled face, slipped his mask off. "What was it, Dad?"
Ed Dory rooted around in the miscellaneous gear in the bottom of the boat and pulled out a small shovel, a relic from his army days. "It's a metal box, but there's a chain attached to the bottom of it, leading down into the sand. Whoever put it there didn't want it found. There was a pile of ballast stone from some old wreck on top of it. The metal isn't corroded so the box must be fairly new." He pulled his mask down. "I'm going back there. Coming?"
"You bet," Bill said, putting his fins on.
Once again down at the site of the strange box, Ed Dory dug in with the shovel underneath the box until he came to a circular piece of metal at the other end of the chain. He dragged the whole assembly over to the anchor line and tied it on. Then, waving at Bill, he finned up toward the boat.
When, back aboard the craft, they had both removed their diving equipment, Ed and Bill hauled up the anchor line with the box and chain attached and examined it closely. It was about a foot and one-half square and made of some kind of dark, heavy-gauge metal. The lid was held down by a double lock. The only markings were a small star in one corner of the underside and the numerals 623373. The chain and the disc appeared to be made of the same metal.
"Let's take it back to the cottage," Ed Dory said. "I don't have any tool heavy enough to open it here." He pulled the starter cord on the outboard motor and they churned across the green expanse of ocean toward their vacation cottage on Key Largo.
Ed Dory was a professor of business administration at North Florida University, but his heavily muscled body, kept in shape by playing tennis and weight lifting, was that of a professional athlete. He had rented the place for a month so that he and Bill could enjoy their first scuba diving in the Florida Keys. A year before, both father and son had gone through a father/son scuba course so as to dive together, but until now most of their diving had been done in the fresh water springs, lakes, and rivers of North Florida. Having the time and a boat to cruise to and explore the many reefs and wrecks off the Florida Keys was a new and exhilarating experience for them, and now the black box had added the spice of mystery to their vacation.