"No," she said with a frown. "Just surprised you don't. That's kind of your thing, you know, history?"
"Sorry. I've been a little busy lately, you know, spending time with the woman I love?"
"Aww," she said with a grin. "I know. And I appreciate that." She changed the subject back to the artwork. "So what does all this mean? There are lots of those circles again. I take it whoever put this here is conveying more passage of time?"
"Most likely. That much we do know, at least now. But there's nothing else." A look of growing concern washed over his face. He pointed his light to either side of the drawings. There was nothing else to see. "I don't understand. Mathews should have left something here for us, a riddle or clue of some kind."
Adriana picked up one of the glow sticks and held it out at arm's length. She stepped cautiously over the rocks, shining the green light on the wall as she moved. "I don't see anything," she said. Eventually, she came to a point where the path ended abruptly in a rock face.
Sean aimed his flashlight back in the other direction and searched the opposite wall for any signs of something Mathews could have left. He, too, found nothing.
"I don't get it," he said as Adriana rejoined him. "It should be here, right? Or am I crazy?"
"The jury's still out on that one," she said. "But you're right. There should be something here. Maybe we're just not thinking about it correctly. What was it the last riddle said again?"
Sean's nearly eidetic memory sprang to life. "The boomerang's water flows into the underworld, another secret kept. We found the secret room. Stands to reason whatever Mathews put here would still be here." He had a gut-wrenching thought. "Unless someone got here before us."
"Maybe," Adriana said. "Or maybe the secret isn't here in this cave. What if it's in the water? After all, the clue suggests that the secret is kept there, not up here."
The realization hit him. "You're right. This whole time I thought it had to be up here in the cave, but that's not what the clue says at all. It's in this pool." He flashed her a look of admiration. "Very impressive, my dear."
She leaned close as if to kiss him. "Why, thank you." Then she yanked the flashlight from his hand and fired a flirty smirk. "Let me take a look. I can hold my breath longer than you."
"I don't suppose telling you no is an option."
Adriana was already tiptoeing cautiously to the water's edge. She glanced back over her shoulder. "You know it isn't."
Before he could protest further, she jumped back in the pool and disappeared below the surface.
"There's no debating with her," he said to himself.
Sean watched her swim all the way to the pool's bottom, following the light as much as he could in the rippling dark liquid. It was difficult to tell what was down there. The water was remarkably clean and free of debris, which made visibility less of an issue for the swimmer.
The light danced off the submerged rocks below as Adriana made her way around the semicircular pool. He noticed her abruptly stop and hover over something. She was halfway around the grotto, and he had no way of being able to tell what she'd found. He didn't have to wait long.
Sean watched as the light streaked toward the surface. Her head breached the air and she spewed water away from her lips. After two short breaths, she turned to where Sean was sitting on the rocks next to one of the glow sticks.
"There's a dead body down there."
The ghastly report caught Sean off guard. "Maybe you should get out of there."
She shook her head. "Whoever it was, they've been dead a long time. I'd guess over fifty years. It's just a skeleton, really. Probably drowned trying to come through that tunnel. I guess they didn't know how far back this thing went."
"You sure you don't want me to look around?" Sean asked.
"No, I'm good. Going to check around the rest of the perimeter."
Again, Adriana tipped over and dove headfirst into the water. Her feet kicked the surface as she knifed down into the blackish pool.
Sean could do nothing but watch as she made her way around the base of the wall. Only a few yards to the right of where Sean was perched, she stopped again. The light fixated on something — what it was, he couldn't tell. She'd been down for about a minute, maybe more. He wished he'd set a stopwatch to keep track.
It started jerking around violently. Sean's heart pounded. His gut told him the worst had happened, that she'd caught her foot in a rock or something and couldn't get it free. He stood up, ready to dive in to her rescue. As he steadied his balance, the light stopped its radical gyrations and went still.
A single horrified thought pierced Sean's mind. Adriana drowned.
Sean jumped out and into the water, making sure he put enough distance between himself and the rocks that he didn't injure himself. Desperation coursed through his veins as he dove downward, cutting through the water with hard, powerful strokes. He pushed his muscles to the max as he kicked and paddled down toward the light near the bottom.
As he drew close to the lithe, white figure, the flashlight suddenly turned up toward him. Adriana blew bubbles out of her nose and then pointed at something in her hand. Then she motioned to the surface with her index finger.
Sean was so relieved he nearly sighed in spite of the fact that he was twenty feet under water. He gave a nod and watched her ascend before he kicked off of the pool floor toward the surface.
The two broke into the cool cave air and hovered for a moment in the water, kicking their legs to keep them above the gentle waves.
"You okay?" Sean asked, trying to cover up the near-irrational concern he'd felt just moments before.
"Yeah. I'm fine. Why'd you come down there?"
Sean felt embarrassed. "I… I saw the light getting yanked around like something was wrong… so I… I jumped in because I thought you were in trouble."
An appreciative smile crept onto Adriana's face. "That is so sweet. You know I can hold my breath longer than that, though."
"I know. I just… I didn't know how long it had been, and I started to worry."
She pulled close to him and gave him a kiss on the cheek. "It's good to know I have a hero for a boyfriend. Now let's see what this thing is."
She held up a stone cube about the size of a baseball.
Sean stared for a moment at the object.
"Come on," she said, and then she paddled away toward the shore. He followed quickly after.
They sat on the slope with their feet still in the chilly water as Adriana passed the cube to him. She pointed the flashlight at it, revealing engravings on four sides of the stone's surface.
On one side, letters and an ampersand spelled out J & M C. Another side featured what looked like an animal paw. The third image looked like it had been defaced, nothing more than a divot dug out of the stone. The last engraving was the shape of a boomerang.
"Well, there's another boomerang," Sean said. "Starting to see a pattern here."
Adriana continued to look at the object. "What do the others mean? You think the letters have something to do with Mathews?"
"Maybe. We need to get back to the others. Been gone a while."
"Don't want Tommy to worry?" she said in an almost seductive tone.
He shrugged. "Yeah. And I'm not totally convinced we're out of the woods yet with whoever was following us."
"You and that intuition. It never shuts off, does it?"
"Sometimes I wish it did."
He tucked the rock into the dry bag, tied it to his ankle like he'd done before, and jumped back in the water.
The two made their way down the shaft and through the tunnel, returning to the daylight that mixed with the churning white water of the falls. Instead of going left when they made it out of the underwater corridor, the two turned right and headed for the landing close to where Tommy said he and Reece would wait.