How had it escaped? The Grool had never even tried to get out of its cage before. In fact, the stupid sponge never seemed very interested in going anywhere. Why did it disappear now? And where did it go?

And what kind of trouble was it planning to make? It couldn't get very far, I told myself. It had no legs.

I started to call to Daniel. But my throat choked with panic.

I frantically started to search for the Grool. I slid on my stomach under the bed. Not there.

I pulled everything out of my closet. I opened dresser drawers. No sign of it.

I checked every inch of the room. I even called out to it: "Here Grool, here Grool."

No. No way. The creature was gone.

The words from the Encyclopedia of the Weird suddenly flashed into my mind: "Anyone who gives the Grool away will DIE within one day."

"Daniel!" I shrieked. "Daniel!" I tore downstairs and into the TV room. I shook him so hard, he dropped his computer mouse.

"The Grool is gone!" I cried. "It escaped!"

Daniel turned away from the computer screen. "Excuse me? What do you mean—gone?"

"It's gone! The cage is empty!" I wailed.

Daniel scrunched up his face, thinking hard. "I know where it is," he said. "Carlo."

"Huh?" I cried. "How could you? How could you let Carlo take it?"

"I didn't let him!" Daniel snapped. "He must have grabbed it when he left. Carlo thinks it's all a big joke. He said there's no way a little sponge can do anything bad."

"What a jerk!" I sputtered. "Maybe we should let him keep the Grool. It would teach him a lesson—a real nasty lesson!"

"Kat, we can't!" Daniel exclaimed. "He's my best friend. We have to get the Grool back from him—before something terrible happens!"

Daniel and I pulled our jackets out of the hall closet. Then we ran out to the garage. We jumped on our bikes and pedaled furiously down Maple Lane.

"Where do you think he went?" I shouted.

"Let's try the school playground," Daniel suggested. "There's always a bunch of kids there."

"Yeah, and Carlo's a big show-off," I exclaimed. "He probably went straight to the playground to show off the Grool."

"He is not a show-off," Daniel protested.

"Is too!" I argued. Pedaling furiously, I shot way ahead of Daniel.

I made it to Chestnut Street a few minutes later. "Only two more blocks!" I called breathlessly. I slowed down so that Daniel could catch up.

I turned the corner. "Oh, no!" I screamed.

I squeezed on the brakes. Stopped short.

Who was that lying in the middle of the street? Was it Carlo?

Yes!

Carlo. Sprawled on his stomach. His arms and legs stretched over the pavement. "We're too late!" Daniel cried. "We're too late!"