Read on for a sneak peek at Billy and Hoover’s next crazy adventure!

Using all of his ghostly strength, Hoover hooked his invisible arm through Billy’s, flipped himself into hyperspeed, and yanked Billy across the art room into the hall.

Billy looked around. All he saw were four kids from his class, supervised by Mr. Wallwetter, practicing for the bow and arrow demonstration. Rod Brownstone took aim and let go of the arrow just as Billy arrived. It wobbled through the air and landed on the floor, about four feet short of the target.

“That was all your fault,” he barked at Kayla Weeks. “You bumped my arm.”

“See, isn’t that amazing,” the Hoove said to Billy.

“I don’t see anything amazing,” Billy answered. “Just Brownstone being a bully, as usual.”

The Hoove turned to Billy and looked closely into his face.

“You don’t see her, do you?”

“Kayla? Sure I see her. It’s hard to miss that whole mess of red hair.”

“No, I mean her. Standing next to Kayla. With the beautiful brown eyes and shining long black hair.”

“You must be seeing things, Hoove. There’s no one there but the teacher and four kids from my class. And no one has long black hair. Unless you count the hair on Mr. Wallwetter’s arms, which I’d rather not.”

“Concentrate, Billy,” the Hoove said. “Feel her presence. Listen for the sound of her voice. And let me know when you see her.”

Billy closed his eyes and concentrated. He didn’t expect to see anything — he was just doing as he was told to get the Hoove off his back. But then, after a few seconds, he thought he heard something. It was a faraway rattle, like pebbles rolling in the sea, following by a faint drumbeat and the sound of a girl’s voice, chanting a strange melody. He opened his eyes, and saw her — a Native American girl, about his size, with long black hair and skin so transparent that she seemed to glow.

The minute she saw Billy gazing at her, an expression of fear darted across her face. As quickly as she had appeared, she disappeared into thin air, leaving nothing in her place but Brownstone’s yapping voice.

Who was she? Where did she come from? And where had she gone?