Nipper squinted at the horse for a moment. Then he stood up straight.

“Step aside,” Nipper said loudly, pushing his sister out of the way. He raised a hand high in the air and wiggled his index finger.

“This is a nose-worthy situation,” he declared, as if addressing an audience. “And I have been called upon to use my special talent!”

Samantha groaned. “Even in Florence, Italy, you are exceptionally gross.”

Nipper plunged his finger deep inside the horse’s dark nostril and pressed. Something gave, a little, and there was a click followed by four loud, low creaking noises. Somewhere deep below the street, it sounded like four giant toilets were flushing. Samantha and Nipper both looked down. The water directly beneath the horses’ feet began to froth.

Nipper took one big step backward to where Samantha stood.

“My work here is done,” he announced proudly, and folded his arms.

The water around the horses began to churn. It looked as if the marble herd was stampeding.

Samantha and Nipper inched back a bit more as the water started whipping more strongly and began to lap against the walls of the fountain.

“Ouch!” said Nipper as a wave tossed one of the coins from the bottom of the fountain and smacked him hard on the cheek with it.

Both kids took another step back.

“Maybe we should get out of the pool for a minute,” Nipper said nervously, rubbing his face where the coin had hit him.

But Samantha was staring at the horses’ feet. A dark shape had appeared in the swirling water in front of them.

Nipper reached for his sister’s hand, but she had already taken another big step back. Samantha turned and looked out from where they stood in the fountain. Several visitors around the plaza had begun to notice the watery spectacle.

“Mommy, it’s a water show!” a boy wearing a New York Yankees T-shirt shouted, pointing at them.

“Prego, non più pagliacci!” wailed a woman standing next to him.

Samantha started to lose her footing. The fountain had become an angry squall.

“Wait!” she shouted to Nipper above the chaos. “I just remembered something Uncle Paul told us about David. That one’s a copy. The real one is in the muse—”

The current yanked Samantha under the surface, ending her sentence in a gurgling “Eeeee!” She was being sucked toward the dark shape in front of the horses. She flailed her arms, slapping at the water helplessly, and slid into darkness.