Dead Secret

couple of things and I’ll be there to help you finish.”
    “I don’t need a break. I’m fine.”
    “All right but don’t tire yourself out. We’ll be there in a few minutes.”
    “No problem.”
    She turned to Mike. “When we finish here, would you go to the entrance to meet Jin? I don’t want him coming into the cave. He’s never done any caving that I’m aware of.”
    Mike nodded, and Diane watched the light from his duel headlamps dance up and down on the walls.
    She led the way, backtracking to the first offshoot tunnel. They picked their way through the rubble to the opening.
    “Here.” She pointed at the mark above the entrance. “There’s no way to know who made it, but it could have been made by our guy to find his way back.”
    “You’re thinking there has to be another entry point,” said Mike, leaning forward to get a close look at the faint X over the entrance.
    “Maybe. Until we made the new hole in the roof of the cavern this may have been a separate cave with its own entrance, unconnected to the cave we came in—unless, of course, one of the passages connects them up somewhere else.”
    Mike squatted and examined the rocks around the mouth of the entrance, moving some of the rock, touching the silt and sand with his fingers. Then he stood and stepped through the opening. Diane followed directly behind him, the passage so narrow that they fit only single file. The tunnel was filled with tight meanders between huge boulders and uneroded protrusions from the wall of the cave. Some of the boulders were caught between other rocks as if they had tumbled down the passage.
    “I don’t like this,” said Mike. “I’m thinking they marked the opening to tell them not to go here. It looks too unstable. Some of the rocks at the entrance have been thrown out from a recent rock slide. Be easy to get trapped if one of these big guys shifts—”
    His voice was cut off by a grinding rumble above them.

Chapter 4
    Mike turned and put a hand on Diane’s back just as she sprang toward the tunnel entrance. A cloud of dust and pebbles suddenly surrounded them, blinding them. Diane kept running, hoping her feet would hit solid ground and not the rocks littering the floor. She sensed Mike right behind her. Her next footfall landed on an angular rock and she started falling. She put her arms in front of her to break the impact but was caught by Mike’s arm around her waist. He carried her for one step; then she regained her footing. They ran out of the tunnel entrance veering sharply away from the path of the rocks. The change of direction and uneven rocky floor threw them both off balance, and the momentum sent them sprawling to the cave floor. By good fortune, they landed mainly on silt and missed the sharp, jagged rocks. Dust bellowed from the opening, followed by a small avalanche of rocks. Mike still held her around the waist.
    “Glad to see I’ve still got adrenaline left; how about you?” said Mike, sliding his arm away.
    “I’m good for another scare or two.” Diane struggled to her hands and knees. Mike rose, pulling her up with him, and they moved away from the dust.
    “Okay, so X means keep out,” he said.
    “It does now.” Diane bent over, coughing the dust out of her lungs.
    “You okay?” Mike choked as he spoke, and he started coughing too.
    “A little beat up, but otherwise fine.” Diane examined the fresh scrapes on the heel of her hands and rubbed her shoulder where it hit a rock. “I’ve never had two close calls in one outing. I don’t have one close call very often.”
    “Sometimes things happen. That’s why we don’t cave alone.”
    “What happened here, do you think?”
    Mike shrugged. “One of the boulders lost its foundation for some reason and gravity took over, sending it crashing into another boulder, and suddenly we had an avalanche.” He shrugged again. “Could have been caused by small seismic activity, sonic boom, who knows . . . like I said, it looked unstable. Wouldn’t have taken much. Judging by the rocks around the entrance, I’m guessing this has happened before.”
    “The entrance looks blocked now,” Diane said, staring at the mouth of the offshoot tunnel still shrouded in a thin fog of dust.
    Mike’s light flickered. He tapped it with his finger. “We’d better do a lamp check.”
    They checked out each other’s headlamps to make sure nothing was broken or loose. During the check, Diane noticed for the first time with some