He kept making circles in the water, paddling slowly to keep afloat despite the heavy feel of his soaked clothes. Then the Mortimer girl was plummeting again, spraying him with water when she struck the surface. She stayed down a long time. He could see her vague shape beneath the rippling waters. Then she was kicking toward the surface again.

When she broke the surface, she splashed water in his face. “You were teasing!” she said indignantly.

“No, I wasn’t!” Owen said angrily. He swam back to the steps himself, marched back up them, and returned to the hole. Water streamed from his hair into his face, and he left huge puddles that drained into the small channels leading to the opening of the cistern. The stone was painted with water droplets and wet shapes the size of feet.

He stood at the edge of the cistern, full of confidence this time. When he jumped back in, he held his body rigid again and allowed himself to sink down. He tried to keep his eyes open during the fall, but as soon as he struck the water, he shut them instinctively. Then his feet touched the floor. As soon as he opened his eyes, he saw the treasures nestled on the floor below. He tried swimming toward one of the chests, seeing a golden ring encrusted with gemstones. If he could grab it and bring it back to her, then she would believe him. But as he struggled, he felt himself floating up away from it, as if something were pulling at his foot. His lungs were burning for air.

He came up spluttering again.

Just like before, the treasure seemed to have disappeared when he looked down below.

The Mortimer girl was staring at him, looking concerned. “You . . . you aren’t teasing . . . are you?”

He shook his head, wanting to swim back down so he could prove it to her.

She grabbed his arm. “Let’s go, Owen. I don’t feel good about this. You were down a long time. I don’t want to drown. Let’s go.”

He felt a strong compulsion to swim to the bottom of the cistern again. Maybe if he let the air out of his lungs, he would be able to stay down longer? Or if he let out his breath before jumping, he could—

“Owen!” she said firmly, sharply. “Come on. We’ll get in trouble if we’re gone too long.” She reached out and gripped his shirt and pulled him toward the canoe. He had the urge to shove her away. There was treasure in the cistern. Maybe it was the king’s treasure. Was this where some of the fountain coins ended up after a wish was granted? His mind reeled with ideas and possibilities. He wanted to take some of the coins. Just a handful. And maybe one of the swords.

In his distraction, the Mortimer girl had managed to pull him back to the stone steps. There was water in his ears and marching up the stone made them feel strange and squishy. She was talking to him, but he could not understand her well. He was seized by the determination to jump back into the water and look again. Maybe he would come back tonight when she was asleep. Then he’d prove it to her.

“There was something down there,” Owen said sulkily.

She looked at him worriedly. “People drown all the time when they’re not careful, Owen. Even little babies can drown in a bucket. Come, let’s get dry.”

When the door shut behind them, Owen heard the click of the latch closing. This time he saw what he had previously missed—a small wire folded by a stone in the wall. It was the latch trigger; they could use the door from either side.

Then they lay down in the stone courtyard, the sun still high overhead. She squeezed the hem of her dress and he listened to the little sounds of the moisture being squished out. They lay, heads just touching, staring up at the blue sky, which had a few fleecy clouds.

“Don’t come back here without me,” she said quietly.

Owen wriggled his finger in his ear because of the tickling water. He ignored her request.

“Owen? Please don’t come back here without me. It isn’t safe to swim alone. My papa taught me that.”

“Why?” Owen challenged. “I’m a good swimmer.”

“So am I,” she said, sounding even more concerned. “But bad things can still happen. Please don’t come back here without me. Promise me.”

“Why do I have to?” he asked, frowning.

“Please, Owen. Promise me you won’t. If you say you won’t, I’ll believe you.”

He felt a darkness brooding in his heart. Resentment. Who was she to tell him what to do? “Will you promise me that you won’t?” he demanded.

“Of course!” she said. Then she turned over and got up on her knees so that she was looking down at him. Her eyes were the color of the cistern water now. She gave him a pleading look. “I promise you, Owen Kiskaddon, that I will not come here alone. This is our secret place. I won’t even tell my grandpapa that we found it. I promise you.”