FRIDAY, JULY 23, STARTED OUT HOT AND sunny, a deceptively fine day for a field trip to Cliff Cave County Park near the Mississippi River south of St. Louis. That morning four adult counselors and 16 youths from St. Joseph’s Home for Boys, a haven for troubled kids, headed to the popular spot for amateur cavers. But two hours after their arrival, heavy rains drenched the area, and as water poured into sinkholes on lop of the cave some of the group turned back. Five boys and two adults stayed behind to explore areas deeper in the cave, like the dark, two-foot-high passageway known as the Drapery Room Crawl. Suddenly they were hit by a wrall of water, a flash flood cascading through the cave. “The water went shoooof!” said Sharon McRoberts, mother of the only survivor. “Everybody got pushed under.”

It was the single worst human tragedy during the seven weeks of rain and flooding that has plagued the Midwest. By late afternoon, nearly a dozen expert cavers had arrived to join firemen and police in the search. Battling a torrent of water, firefighters had already found the bodies of counselor Darnell Redmond, 31, and two boys Emmett Terry, 9, and Tarrell Battle, 10—in a swollen creek just outside the cave. “I thought, ‘Well, if three are dead already, the rest are probably also dead,’ ” recalls caver Bob Cline, 39, an engineer at an electric company. “But I also thought there was a chance someone could find an air pocket and survive.”

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Outfitted with wet suits and helmets with built-in lights, the rescuers waded and crawled into the dark, flooded passages. About 100 feet in, they found the body of Melvin Bell, 10, then nothing for the next four hours. At 10 p.m. they had to quit for the night with a counselor and two boys still missing. “By that point,” says caver Rich Schleper, 43, a body-shop foreman, “we fell there was no way anybody could have made it. But you pursue that one-in-a-million chance.”

The next morning rescuers split up into teams for another sweep through the cave. Even though 20 hours had passed since the flash flood, they were not about to give up. “There’s always hope,” says Cline. “Thai’s the only reason you go back. It’s very faint, bill there’s always hope.” This time the water had receded a little. The cavers followed standard procedure. “You crisscross,” explains Schleper, “zigzagging back and forth, feeling with your hands and feet in case somebody’s down there.” A half hour into the cave, Schleper heard something. “I (old everyone to be quiet,” he says. “We listened and didn’t hear anything. Then we heard it again.” At first, Schleper thought the sound was coming from another group of rescuers. “Then it dawned on us: It was coming from the wrong direction,” he says. “Someone yelled, ‘We’ve got a survivor!’ ”

They found 13-year-old Gary Mahr huddled in chill, ankle-deep water. He was shivering violently and all his clothes, except for his shorts, had been torn off by the deluge. “He had a scared-to-death look in his eyes,” says Schleper. “I can just imagine how horrible it must have been for him—his head basically in a crack in the ceiling, with water rushing by, in total darkness.”

Gary saved himself, his mother said later, by remembering something his aunt, a lifeguard, had told him once: “Whenever you’re in a danger zone swimming, don’t panic.” So Gary kept his head, even though he realized bodies were floating past him. He coolly kept reaching for air pockets along the roof of the cave, so he could come up and breathe. “I did that for about an hour,” he said. “Finally I got to an air pocket where I could hang on, and I held on until the water went down. I was praying somebody would discover me. And they did.”

The rescuers did not move Gary immediately. Concerned that he was suffering from hypothermia, they wrapped him in a space blanket to warm him up. “His joints were too stiff to move from being there all night,” says Cline.

While they waited, one caver scrambled outside to alert medical personnel. Later, rescuers found the bodies of counselor Jennifer Metherd, 21, and 12-year-old Terrill Vincent 150 feel up the passageway.

As he was warming up, Mahr asked rescuers about his friends who had stayed in the cave with him. “We looked al each other,” recalls Steve Every, a 36-year-old mechanic and caver. “I said, ‘Let’s tell him the truth.’ ” When the rescuers told Mahr that the bodies of his friends had been found, Mahr “look it very well,” recalls Every. “He knew.” After that, says Every, “We congratulated him on being a very brave kid.”

The tragedy raised many questions. Local officials were upset that the boys’ home took the children caving when the park was officially closed because of the danger of flash floods. Thai danger was very real, experienced cavers say; the forecasts that day were for more rain and possible flash flooding. Meanwhile, Catholic Charities, which runs the home, complained that there were no warning signs other than one marked “Road Closed.” And officials al St. Joseph’s said other groups had visited the cave earlier in the week. The matter is under investigation, but for the grieving families there is only rage and pain. “I just should never have happened,” said Joan Hoff, Jennifer Metherd’s aunt. “Their deaths were for nothing.”