“Yes, but the lake is an ideal testing ground. It’s large, lightly populated, and features depths of over a thousand feet. Our work here focuses on research in advanced hull and propulsion designs—ones that allow for submarines to operate with a minimum acoustic signature. The lake is a nearly perfect controlled environment in which to test new designs and technologies.”

“The Sea Jet being a test platform?” Pitt asked.

“Exactly,” Nichols said. “It’s what we call an Advanced Electric Ship Demonstrator. Though it looks a bit like a submarine, it is actually a quarter-scale model of the new DD(X) class of destroyer. We’ve used it to experiment with some radical new hull designs and propulsion systems. It was originally built with waterjet propulsion, but we’ve migrated to some other technologies I probably shouldn’t talk about. We were scheduled to test Carl’s latest tinkering related to the Sea Arrow project, but we’re at somewhat of a loss there now.”

“The technology in the Slippery Mumm?” Ann asked.

“Yes. He was here testing it in the lake just a few weeks ago. I remember him telling the boys that he was really going to be scaring the fish with it. A couple of the fellows were out on the lake at the time and they claimed he was registering some crazy speeds.”

“Didn’t he work on it here at the facility?”

“Not much. He’d come in and run things on our computers, but he was always three steps ahead of us. When he was in town, he was usually holed up at his cabin with Manny, tinkering away.”

“It’s important that we find and secure all of his research related to the Slippery Mumm,” Ann said.

“I already received that request from the folks at DARPA and I’m pulling together what we have,” Nichols said. “The fact of the matter is, Carl maintained ninety percent of the data. What wasn’t in his head is probably still out at his cabin. Here, let me give you the address.”

He checked his Rolodex and jotted down the address for Ann, giving directions as he wrote. “There’s a rusty bell sitting on the patio table in back. Underneath it should be his spare keys to the house and boat.”

Ann gave him a How did you know that? look.

“I’ve downed more than a few beers with Carl on his porch and his boat,” Nichols said with a wink.

Ann thanked him for his time, and they were escorted back to the front gate. Ann felt a sense of optimism for the first time. “See, I think this little side trip is going to pay off. Let’s go check out Heiland’s cabin, and then I’ll call the FBI to come secure the place.”

“No objection to having dinner first?” Pitt said. “It’ll be getting dark soon.”

“Only if I can buy.”

Their options in the small town were limited. Pitt selected a waterfront restaurant called the Captain’s Wheel just down the road. Ann sampled a Greek salad while Pitt polished off a cheeseburger and beer as they watched the marina lights begin flickering on.

Ann noticed a tranquil look cross Pitt’s face as he gazed at the lake’s still waters. There was something enigmatic about the man, yet she felt entirely safe with him. She had met him just days before and knew almost nothing about him—other than the disappointing discovery that he was married.

“I’m not sure I ever thanked you for saving my life in Tijuana,” she said.

Pitt looked at her and smiled. “I’m not sure jumping aboard a boat filled with armed thugs was the smartest act of law enforcement I’ve ever seen, but I’m glad things worked out.”

“I’m occasionally prone to rashness.” She thought of her uninvited visit to his cabin the night before. “I’m hoping that we can be friends in Washington after this case is resolved.”

“I’d like that.”

With a grin he slid the check across the table to her. “But for now, how about we go find Heiland’s cabin before it gets completely dark.”

Nichols had told them they couldn’t get lost and he was right. His directions sent them down a single-lane road that skirted the Acoustic Research Center and continued along the southern edge of the inlet. They passed clusters of cabins that grew fewer in number as the town lights receded behind them. The road tracked toward the bay’s entrance, then turned south, following the lake’s irregular shore. They drove another few miles before the road ended in a pine-clustered cul-de-sac. A narrow gravel drive led to a red wooden house facing the water.

“That looks like the place,” Ann said, confirming the address on a mailbox.

Pitt drove the rental car down the drive and parked beside an attached garage that looked large enough to house a dozen vehicles. No lights were on in the house, and a desolate silence permeated the grounds.

Ann noticed the first stars visible overhead as she felt a light breeze blow in from the lake. “I wish we had a flashlight,” she said, poking her crutches at the uneven ground that sloped toward the lake.

“Why don’t you just head for the front door and I’ll go look for the keys out back,” Pitt said.

He stepped around the side of the garage and followed a footpath to the rear of the house. Just a thin band of tall pines separated the backyard from the water. Pitt could tell the house sat on a prime parcel of land that offered a breathtaking view of the lake. He swatted at a mosquito buzzing in his ear as he stepped onto a wide porch that ran the length of the house. He quickly spotted the old bell centered on a coffee table surrounded by some Adirondack chairs. The keys were indeed there, attached to a floatable chain used by boaters. Retracing his steps, he glanced toward the lake, noticing a private dock at the property line with a dark-colored boat moored alongside.

Ann had made her way to the front door and stood resting on her crutches. “Any luck?”

Pitt dropped the keys into her hand. “Just as advertised.”

She unlocked the door and stepped inside, groping for a switch. Pitt followed her in as she flipped on a bank of overhead spotlights that illuminated the interior. The antique cabin had been tastefully updated over the years. The kitchen glimmered with stainless steel appliances and granite countertops, while the living room featured a large flat-panel television. A pair of stuffed trout hung next to an antique fly rod above the rock fireplace, an ode to one of the owner’s longtime passions.

Uncomfortable scouring the dead man’s refuge, Ann quickly hobbled through the house searching for an office or workshop. All she found were four large bedrooms.

“We better hope there’s something in the garage.” She looked toward a door at the end of the hall.

Pitt followed her as she opened the door and flicked on the lights. The sight surprised them both.

Though they expected to find a workshop of some sort, they never anticipated that a top-drawer research lab would be hidden in the Idaho woods. The garage looked like it had been transferred from the heart of Silicon Valley. The bright overhead lights illuminated a spotlessly clean white room filled with stainless steel workbenches. Rack after rack of electronic test equipment lined one wall; another corner was set up as a fabrication area. A long, narrow tank filled with water, used for marine hull and propulsion testing, stretched nearly the length of the building. But the space wasn’t entirely devoted to work, Pitt noted. In one corner stood a 1950s-era pinball machine next to an elaborate espresso machine.

“Jackpot,” Pitt said.

Ann limped her way across the room, where a large executive desk was positioned next to two easy chairs. A pair of laptop computers sat open beside several bound journals and stacks of schematic diagrams. Ann picked up a journal and read a few lines of the handwritten notes.

“This is dated just a few days ago,” she said. “He describes a series of successful tests of ‘SM’ in the lake and his plans for a final saltwater proof run in San Diego.”