She let go of the vines and dropped down. Her face was still visible from the window. She beamed at him. “Not far! Come on!”

Owen listened for sounds of anyone approaching in the corridor, but heard nothing. He climbed up onto the windowsill on his own and scooted off and jumped. There was brickwork on the ground outside and the shade from the vines helped conceal him and the Mortimer girl. He reached back and slowly shut the window, making sure to leave it ajar so they could get back in.

There was ivy everywhere, smothering the wall. She had a leaf of it sticking to her hair as she peered at the walled-in courtyard.

There was the well hole in the middle.

“Come on,” she whispered, taking his hand and starting to creep forward. They both looked and listened for any warning sounds. Their boots scuffed on the bricks. Owen gazed up and saw Ankarette’s tower. If she was looking out the window, she would be able to see them. The sun was high overhead, making their shadows small at their feet.

“I love wicked ideas like this one!” she said with delight, searching around for any signs they’d get caught.

They approached the well hole. It went down like steps. There were runners and gutters that led to the eight points, and he could discern a slight slope in the bricks. This well made the water run down into it.

“So, this is the cistern?” Owen said. They reached the outer rim and stared down into the huge dark circle.

“That’s what my grandpapa said. It collects rainwater during the winter. It goes under the palace quite a ways. That’s why there’s no dungeon. The palace was built on a cistern!”

Owen had never heard that word before she had first said it to him. The black gaping hole was wide enough that they could have stood across it without being able to reach each other. But he intuitively understood the structure. “It doesn’t lead to a water spring, which makes sense since the palace is on a hill. It would be hard to carry water up from the river every day.”

“Exactly!” she said excitedly. “The cistern catches the water and holds it.” She stepped down into the first ring of stones, trying to pull him along, but he yanked his hand away.

“What are you doing?” he asked, his stomach twisting with fear.

“I want to look down!” She tried to take his hand again, but he stepped back. “Oh, come on, Owen! Let’s just look!”

He was curious but cautious. His brush with danger outside the king’s chamber had rattled him, and he wasn’t feeling very courageous.

“Hold on,” he said. He wanted to come down at his own pace. She shrugged and hurried to the edge so she could kneel down and stare into the abyss. Her eyes lit with wonder. “Look how deep it is!”

Owen frowned. There was no way he was going to let her enjoy it all by herself. He stiffened his lip and marched down to the edge. “Move over.”

She scooted to the side and their heads almost touched as they leaned in. He felt her hair brush against his. It made him feel . . . funny.

The cistern was half-empty. The waters rippled beneath them and he could see their own reflections warped on the placid surface. The chamber was deep, very deep. There were columns of stone and buttresses supporting it. There were numbers and little gashes carved into the column nearest the hole. The numbers meant how deep the water was and he could tell by the numbers at the top of the column that the cistern was just over half-full.

“There is a lot of water down there,” he announced.

The Mortimer girl brushed hair over her ear and gripped the edge of the cistern opening before lowering her head deep inside.

“Hello!” she called out, and her voice echoed. Owen thought she was insane.

“Why did you call out?” he demanded.

She pulled her head back up. “I wanted to see if there was anyone down there. Maybe there’s a water sprite!”

“Water sprites aren’t real,” Owen said stiffly.

“Yes, they are,” she contradicted.

“Have you ever seen one?”

“Just because I haven’t doesn’t mean they’re not real. Don’t be stupid, Owen. Of course they’re real. Papa said so. He said there is treasure under the deepest fathoms of the sea. Ancient swords that can’t rust. Magic rings. There’s another world there that we can’t see. The ocean is its own kingdom.” She looked him in the face, her eyes wide and sincere. “I’m not making up stories, Owen. It’s true. The people who drown are those who try to join the water sprites but fail. They fail because they’re afraid.” She gave him a determined look. “I’m not afraid.”