“I wonder what the Nevada Gaming Commission would say if they knew there were four nuclear bombs under the casino.”

“They’d probably care less,” said Weatherhill. “So long as his dealers aren’t mechanics.”

“Mechanics?”

“Cheats for the house.”

He pulled the Avanti to a stop at the main entrance and tipped the doorman, who removed their luggage from the trunk. An attendant parked the car, and they registered at the front desk, Stacy looking starry-eyed and smiling demurely in an attempt to seem like a new bride, an event she had trouble remembering in her own past.

In their room, Weatherhill tipped the bellman and closed the door. He immediately opened a suitcase and removed a set of blueprints of the hotel and spread them on the bed.

“They’ve sealed the cars inside a large vault in a third-level basement,” he said.

Stacy studied the sheet showing the plan of the entire lower basement and a report from one of the surveillance team. ” ‘Double reinforced concrete with a steel overlay,’ ” she read aloud. ” ‘One large steel door that raises into the ceiling. Security cameras and three guards with two Dobermans.’ We won’t be breaking in from the front. Easy enough to beat the electronic systems, but the human factor and the dogs make it tough for just the two of us.”

Weatherhill tapped a section of the blueprint. “We’ll go in through the ventilator.”

“Lucky for us it has one.”

“A requirement in the construction code. Without ventilation to prevent expansion and contraction of the concrete, cracks could form and affect the foundation of the hotel.”

“Where does the vent originate?”

“The roof.”

“Too far for our gear.”

“We can make entry from a utility room on the second underground parking level.”

“Want me to go in?”

Weatherhill shook his head. “You’re smaller, but nuclear devices fall in my department. I’ll make the entry while you handle the lines.”

She examined the dimensions on the ventilator duct. “It’s going to be a tight fit. I hope you’re not claustrophobic.”

Carrying tote bags and rackets and dressed in white tennis togs, Weatherhill and Stacy passed unobtrusively as a couple going to play on the hotel courts. After waiting for an elevator free of people, they rode it down to the second-level parking garage, where Weatherhill slipped the lock on the door to the utility room in less than five seconds.

The small interior was laced with steam and water pipes and digital-dialed instruments that monitored temperatures and humidity. A row of cabinets held push brooms, cleaning supplies, and jumper cables for stalled cars in the parking area.

Stacy quickly unzipped their tote bags and laid out a variety of equipment as Weatherhill donned a nylon one-piece suit. He clipped on a Delta belt and body harness, attaching it around his waist.

Stacy then assembled a spring-powered piston tube with a wide-diameter barrel oddly called a “beanbag gun.” Then she attached it to a “hedgehog,” a strange object that was covered by round ball bearing-like wheels with a pulley in its center. Next she uncoiled three lengths of thin nylon line and connected them to the hedgehog and beanbag gun.

Weatherhill consulted the blueprint showing the ventilating system for the final time. A large vertical shaft falling from the roof joined smaller ducts that ran horizontally between the ceilings and floors of the parking areas. The duct running to the vault that held the bomb cars ran between the floor beneath their feet and the ceiling of the basement below.

He took a small battery-operated electric saw and began cutting a large hole in the thin sheet-metal wall. Three minutes later he set aside the cover, took out a tiny flashlight, and beamed it inside the duct.

“It drops about a meter before branching out toward the vault,” he said.

“Then how far?” Stacy asked.

“According to the blueprint, about ten meters.”

“Can you get through the elbow where the duct curves from vertical to horizontal?”

“Only if I hold my breath,” he replied with a slight grin.

“Radio check,” she said, setting a miniature microphone and receiver over her head.

He turned and whispered into a tiny transmitter on his wrist. “Testing, testing. Am I coming through?”

“Clear as crystal, and me?”

“Good.”

Stacy gave him a reassuring hug and then leaned into the ventilator and pulled the trigger on the beanbag gun. The springloaded piston shot the hedgehog into the darkness, where its momentum and roller bearing wheels took it smoothly around the bend. They could hear it sailing through the duct for a few seconds, dragging the three nylon lines behind it, before there was an audible clink, signaling that it had stopped on impact with the filter screen set in the vault’s wall. Then Stacy pulled another trigger, and twin rods shot out of the hedgehog against the sides of the duct and jammed it solidly in place.

“I hope you’ve been working out at the gym,” said Weatherhill as he slipped the rope through the clips in his harness. “Because your little old muscles will be taxed tonight.”

She smiled and pointed to a pulley she’d already attached to one line and a water pipe. “It’s all in the leverage,” she said slyly.

Weatherhill clamped the small but powerful flashlight around one wrist. He bent down and took what looked like an exact replica of an air-conditioning compressor out of his tote bag. He had constructed it to replace the one he was about to steal. Then he nodded. “Might as well get going.”

He leaned into the vertical shaft and slowly dropped down headfirst, extending the dummy compressor beyond his head as Stacy took up the strain on one line. There was plenty of room here, but when he came to the elbow into the horizontal duct, he had to contort his body like a snake and squeeze through. He entered on his back in order to bend his body around the narrow curve. And then he was in.

“Okay, Stacy, pull away,” he spoke into his wrist radio.

“How’s the fit?”

“Let’s just say I can hardly breathe.”

She pulled on a pair of gloves and began to heave on one of the nylon ropes that wound around the pulley on the hedgehog and attached to Weatherhill’s harness, pulling him through the narrow confines of the ventilation duct.

He could do little to help her, except exhale when he felt her tug on the rope. He began to sweat inside the nylon suit. There was no air-conditioning running through the ventilator, and the outside atmosphere that wafted down from the opening on the hotel roof was hot and stifling.

Stacy wasn’t enjoying mild temperatures either. The steam pipes that ran through the utility room kept the heat and humidity close to that of a steam bath.

“I can see the hedgehog and ventilator screen,” he reported after eight minutes.

Another five meters and he was there. The blueprints had not shown any TV cameras in the vault, but he peered into the darkened interior for signs of them. He also removed a small sensor from a sleeve pocket and checked for laser or heat-seeking scanners. His inspection thankfully came up dry.

He smiled to himself. The elaborate defense and alarm measures were all on the outside of the vault, a flaw that was common in many security systems.

He twisted off the screws, tied a small string to the screen and lowered it to the floor quietly. He slipped the lever that released the hedgehog anchor prongs and lowered it into the vault along with the bogus compressor. Then he slowly descended headfirst until he finally rolled onto the concrete floor.

“I’m inside,” he told Stacy.

“I read you.”

He shined the light around the vault. The bomb cars seemed doubly menacing, sitting ominously in musty blackness and surrounded by thick concrete walls. The awesome destruction in such a cloistered area was difficult to imagine.