"l don't think so," Cassie said. "l'll bet this is something more medical. Besides, we'd smell blood if the other sharks were getting hurt."

"Unless they're getting boiled alive," I said. "Boiled and canned, and in one process. Then it's Chicken of the Sea shark meat." Suddenly I heard Cassie yell, "Ahhh!"

She was right in front of me. And before I could react, I knew why she had yelled. Steel claws reached out from each side and grabbed me just behind my hammer head. The claws held me tightly, but not painfully. I was drawn upward till I was vertical. I was out of the water. My gills gasped in the air. My body writhed in panic.

I saw a line of us. A conveyor belt of hammerhead sharks, all hanging vertically. There were

human-Controllers and Hork-Bajir manning equipment boards and looking totally uninterested.

We turned a corner into a second room and up rose a robot arm festooned with tools whose purpose I couldn't even guess. The robot arm arced toward the shark two spaces ahead of Cassie. From out of nowhere a long, thick needle appeared. It plunged into the back of the shark's head.

"What the ... We have to get outta here!" I cried.

But there was no time. The conveyor belt kept moving. Too fast!

The robot arm moved with machine precision. It plunged the needle into the back of Cassie's head.

"lt's okay," Cassie managed to gasp. "l think it was just an immunization. Maybe."

But what came next was not okay. The robot arm hesitated. It popped out a sort of meta! detector or something and moved it over Cassie's shark head. Then it extruded a drill.

Not like a dental drill. Like a drill you'd use to make holes in wood.

The drill bit spun and it plunged.

"What was that?!" Cassie cried in alarm.

The drill bit withdrew. But a bright steel probe lanced into the hole.

In it poked, then

withdrew. A wisp of smoke curled away from the hole as it was cauterized by a green laser beam.

"Cassie! Are you okay?" Jake yelled.

"Uh . . . yeah. I guess so."

And then it was my turn. There was a sharp prick of pain, but sharks don't care about pain.

The drill withdrew. And seconds later, I was dropped into saltwater. In fact, I quickly realized, I was back in the same boat dock I'd been in before. There were other hammerheads all around me. My friends were being dropped practically on top of me.

"What was thata\\ about?" Tobias asked.

"They injected us all with something," Cassie said. "Right into our brains. But... oh. Oh! Aaaarrggghhh!"

It hit me a few seconds later. How can I describe the pain? You know how I said sharks don't care about pain? Well, this wasn't any pain that any shark had endured. I felt my brain exploding. Like some mad animal was trapped inside my head and trying to claw its way out.

I screamed. "Aaaahhhhh! Oh, oh, oh! Stop it!"

And then, through the water, a sound reverberated. Like a WHOOO-WHOOO-WHOOO.

The pain stopped. In its place came a wave of pleasure. It was like the taste of prey in my shark mouth: the ultimate shark pleasure.

"What is happening?" Ax demanded.

"l don't know, but it's kind of nice."

Then, the weirdest thing ... I felt the shark mind, that simple killing-machine mind, seem to open up. The shark mind looked out through its eyes, and for the first time ever, noticed things that had nothing to do with finding prey.

The shark eyes noticed the pattern of the corrugated steel that formed the dock. The shark sense of smell took note of scents like oil and rust and seaweed that had nothing to do with killing and eating.

"This sounds insane," I said, "but I think this shark is getting srnarter."

"Like the sharks that attacked us," Rachel agreed.

"My shark brain just wondered," Cassie said, sounding amazed. "lt wondered whether there would be prey later."

"That sounds sharklike," Jake said.

"No!" Cassie yelled excitedly. "Sharks don't "wonder." Sharks can't even form the concept of a future, let alone wonder about it. It's completely impossible!"

"So what does it mean?" Tobias asked.

Cassie answered. "!t's the Yeerks. They've altered these brains. That's why the sharks were able to work together the other time. The Yeerks are mutating these shark brains. We just got the first treatments

"Why?" Rachel wondered.

Ax said, "There's only one reason to alter the physiology of these brains. To make it possible for the Yeerks to enter them. The natural shark brain is too small, too simplistic for the Yeerks to control. They are mutating the sharks to make them capable of being made into Controllers. They will need to add ear canals as well. So that the Yeerks can enter and leave the brain."

"A new version of Hork-Bajir," I said. "That's it! The Yeerks want water-going Hork-Bajir. They need dangerous, tough, deadly shock-troops that can go where Hork-Bajir can't: in the water. What better soldier than a s/7a/7r-Controller, if you need troops in an underwater environment?"

"Yes," Tobias agreed grimly. "And what worse nightmare for any peaceful species to face?"

"We have to find out more," Jake said. "lt's time to get out of the water and go look around in this place."

It was going to be hard and dangerous. We had to return to human form.

Then morph again. All in the water. Without being seen, or drowning.

I was relieved to be getting out of the shark morph. I hated sharks, I'd decided. I didn't want to be one anymore. Let alone a sort of super, self-aware, thinking shark.

I was happy when my legs reappeared. When my fins became hands, when my teeth ground and itched away and became the tiny, blunt, pitifully weak human teeth.

But I knew I'd never hold my breath clear into

a new morph. I poked my head above the surface and looked around with human eyes for the first time. The others popped up nearby. Tobias looked like a drowned rat. He stood on Rachel's head.