“DO YOU THINK HE BOUGHT IT?” EMMET ASKED.

“There’s no reason to think he wouldn’t,” Dr. Geaux said. “He has no idea we discovered his surveillance. We had the FBI sweep the parking lots and outside the buildings. They didn’t find anything aside from the camera in the lab and two audio feeds in the main office.”

“He’s just … Wouldn’t he think it would be uncovered eventually? He’s always thinking ahead,” Emmet said.

Emmet considered himself the world’s foremost Dr. Catalyst expert. From the time he and Calvin had rescued his father, Emmet understood Dr. Catalyst had an elaborate plan in place. Twice now they had stopped him, and yet he kept going, creating more creatures, endangering more people.

“It’s possible. We’re dealing with someone who is smart, crazy, and determined, and that’s always a bad combination,” she said.

They were driving in one of the task force SUVs along US 1 toward Miami. A few miles ahead, a member of the task force drove Dr. Doyle’s truck. After Dr. Geaux and his dad had carried the Pterogator outside the lab, they switched up. An agent dressed in identical clothing to what his dad was wearing drove off in the truck, with a body bag stuffed full of rocks and newspapers in the back. The truck had four undercover cars trailing it, two in front, and a helicopter watching from high in the air. The state lab in Miami was also filled with agents and cops, ready for whatever might happen.

The SUV their group drove was a super-tricked-out law-enforcement vehicle. From their rear seats, Emmet and Calvin could watch the video feed from the helicopter on monitors that flipped down from the ceiling.

“Why would he care about getting back his Pterogator corpse enough to carjack my fake dad?” Emmet asked.

“We don’t know that he will,” Dr. Doyle answered. “But my guess has always been that we have his first viable Pterogator or one of his very early clones. I think, as a scientist, he’s burning to get it back, and to know what happened to it. And if he thinks there’s even the remotest possibility we could trace him through the amino-acid compounds he used, he’d try to prevent us from testing the corpse.”

As head of the task force, Dr. Geaux was letting the professionals tail Dr. Doyle’s truck. When Emmet heard about the plan, he insisted that he and Calvin be allowed to be there when Dr. Catalyst was arrested. Dr. Geaux, of course, refused. In the ensuing argument, Emmet had played every sympathy card he possessed, including pouting with his swollen face, until Dr. Geaux finally agreed. They would trail several miles behind the agent driving his dad’s pickup, but once Dr. Catalyst was arrested, Emmet could have his moment. So he and Calvin sat in the back, glued to the monitors, while Dr. Doyle rode shotgun.

The screen showed his dad’s truck driving along a stretch of road that was surrounded by swamp on both sides. Even the ground in Florida is water, Emmet thought. Or watery. Or a sponge. Whatever, he didn’t like it. Ground should be solid.

A lot of police lingo came over the monitor as the officers and agents communicated with one another. The upshot of all the “Copy thats,” and “10-4s,” and “No suspect sighteds” was that so far no one had spotted anything suspicious.

Emmet couldn’t stand the tension. Every time a voice came over the radio, he leaned forward in the seat, staring at the monitor.

“Dude, you need to relax,” Calvin said.

“I’ll relax when he’s enrolled at Convict College,” Emmet said.

“Where?” Calvin asked.

Emmet shrugged. “Jail. I watched a prison documentary on TV the other night.”

Calvin sighed.

The radio crackled with static, then a voice spoke up that Emmet recognized. It was Stuke’s dad. He was a Florida City cop and had joined the task force after Stuke was attacked by the Muraecudas. He was probably the one person who wanted Dr. Catalyst caught as much as Emmet did.

“Unit one, I’ve got eyes on a gray, late-model Pontiac sedan. It’s been following the truck for the past six miles, over.”

“Copy that, unit two. Can you ID a driver?”

“Negative, unit one, tinted windows,” Stuke’s dad answered. “Bring up unit three to my position, I’m pulling off at the next exit, then I’ll move to the back of the line. Keep rotating. Everyone stay calm. If it is him, we don’t want to spook him. Chopper one, do you have him?”

“Copy that, unit two,” the pilot answered.

The camera from the helicopter pulled back, and they could now see the tiny image of the pickup driving down the road. About a quarter of a mile behind it was the gray sedan. Emmet couldn’t tell which of the other vehicles was being driven by the undercover cops.

He sat up even straighter in the seat now, as did Calvin. There was tense, unbearable silence on the radio for several seconds.

“Unit one, this is unit three. Sedan is accelerating. It’s closing on the truck.”

Emmet clinched his fists.

“Unit one, this is chopper one. It’s two car lengths back. Unit three, move to intercept.” Emmet marveled at how calm they remained on the radio.

“Negative, unit three, negative. They could be passing. Hold …”

“All units! All units! This is unit three, gray sedan just rammed the truck. All units converge! All units conver — Whoa!”

Emmet watched everything unfold like it was in slow motion. The gray sedan shot forward and rammed the rear end of the pickup. The driver of the pickup fought for control, swerving slightly to the right. At that point, the gray sedan pulled out and sped forward alongside the truck, turning in an attempt to push the pickup off the road. But the truck hit the brakes just enough so that the sedan traveled too far forward and was now being pushed along by the pickup.

The gray car turned sideways, its tires digging into the pavement, and it suddenly flipped several times, riding up along the guardrail at the side of the road and then tumbling over it into the swamp.

“What just happened?!” Emmet cried.

“I don’t know,” Dr. Geaux said. She grabbed the microphone on the radio and started talking into it really fast.

“We’ve got the sedan! All units, there has been a collision, repeat, the sedan has gone over the embankment into the water,” Lieutenant Stukaczowski said over the radio. “Get EMS and paramedics out here! All units respond, code three!”

Dr. Geaux hit the lights and sirens on the SUV and accelerated into the passing lane. A few miles later, a long line of cars was stopped in the road. Ahead of them, the light bars of numerous emergency vehicles flashed over the accident scene. Dr. Geaux steered their vehicle onto the shoulder, blowing past the backed-up traffic. When they arrived, the pickup truck was crunched against the guardrail, its right side dented up pretty badly, but the driver was standing beside it and appeared to be okay.

“All of you stay inside this car,” Dr. Geaux said, slowing the SUV and slamming it in park. She opened the door and rushed toward the scene.

They watched the flurry of activity for several minutes. There was constant chatter over the radio. On the monitor they could see Stuke’s dad and several other law-enforcement agents gesturing and waving their arms. Two men pulled rifles from their vehicles and stationed themselves next to the road where the gray sedan had gone into the swamp.

“Why do those guys have rifles?” Emmet asked. “We want him alive!”

“Gators,” Calvin said. “If they send somebody into the water to go after the car’s driver, there could be gators nearby. If they come after the rescuers, then those officers will shoot them.”

“Remind me never to learn to drive as long as I live in Florida,” Emmet said.

Two police officers waded into the swamp. The gray sedan had gone in rear-end-first, but the chopper was too high to see everything clearly. Emmet looked out the window to see a tow truck pulling up in front of them, blocking their view.

Emmet put his hand on the door handle.

“Don’t even think about it,” his dad said from the front seat.

“But — !” Emmet protested.

“Not a chance,” Dr. Doyle said.

They waited. The radio was silent. Finally, Dr. Geaux appeared, coming around the side of the tow truck and walking toward the SUV. She did not look happy as she opened the door and climbed back in the driver’s seat.

“Who was it? Did you find him? Is he alive?” Emmet started peppering her with questions, but stopped when Dr. Geaux pounded her hands on the steering wheel in frustration.

“It was no one. He played us. The car was empty. He had a remote operating system driving the car. He must have suspected all along that we were trying to set him up.”

“How did he know?” Emmet said, barely able to conceal his disappointment.

“I wish I knew, Emmet,” she said. “I wish I knew.”

The line of stopped cars behind them grew longer and longer. The police finally shut down the highway and allowed drivers to turn around in the median and travel in the opposite direction. Amidst all the confusion and chaos, no one noticed the late-model pickup that followed suit, bouncing slowly across the grass between the divided highway, and then onto the road heading back toward Florida City.

Where it sped quickly away.