“If my husband sent you—”

“He didn’t send me,” Henry interrupted. “He invited me. I’m sorry, and I sure don’t mean to cause you any alarm. I work for the United States Marshals Service. Here’s my identification papers—Mr. Lincoln said you’d want to see them. I was born in Mobile, and I never managed to shake the vowels; but my parents were scalawags, not fire-eaters, and now we’re all living in Baltimore. Please, ma’am. I’m here to help.” And then he added quickly, “Oh, Mr. Lincoln said that if you still didn’t buy it, I should say that there’s a Pinkerton agent on the way to your home right now, arriving from Chicago.”

Gideon unfroze, and returned his gun to its place against his back.

Mary also relented. “Chicago,” she repeated. “That was the code word we picked between us. Hello, Mr.… Epperson? Am I reading this right?”

“Yes, ma’am,” he said. “It’s a pleasure and an honor to meet you.”

Gideon found his way to the basement steps and climbed them, emerging into a late afternoon that wasn’t fully dark yet, but would be in another twenty minutes. “You’re the man from the Marshals Service?” he said, not because he doubted it, but because he didn’t want to sneak up on anyone with a gun. Mary was worrisome enough all by herself, never mind the armed federal agent.

Henry turned around, holding a wallet of folded papers. He was somewhat taller than Mary, and somewhat shorter than Gideon, with light hair and round, wire-rimmed glasses. He was casually but warmly dressed, though he wore no gloves. “Yes, that’s me. You must be Dr. Bardsley. Just the man I’m here to see.” He held out his hand. It was chapped and pink, but his nails were clean.

Gideon shook it. “Yes. And if you’re here to clean up the Jefferson, I hope you’ve brought heavy machinery, construction equipment … something big enough to move this mess.” He almost suggested a miracle, but restrained himself.

“Well now. I’m happy to lend a hand if a hand is needed, but I didn’t bring anything big enough to make a dent. Those fellows really did a number on the place. But I hear they didn’t get what they came for.”

“No. Not that the machine does us any good, down there in that crater. I still can’t tell if its power source is operational. It’s a rabbit warren under there, and dark as a grave. So if you’re not here to dig, and you’re not here to open fire, what brings you to … to what’s left of my laboratory?”

“My dirigible got a good tail wind, I guess, which is how I arrived at your home so early,” he said to Mary. Then, to Gideon: “And since I landed ahead of schedule, Mr. Lincoln sent me here with word about your mother and nephew.”

For one white-hot moment, a flare of pure, distilled rage seared Gideon’s vision. It was a familiar, hateful thing—a thing he usually kept in a box in the back of his brain, labeled “do not open” and stashed under the plans for the Fiddlehead and other inventions. He’d boxed up that fury on the road from Washington to Tennessee one night, under cover of darkness with the family members who’d agreed to join him.

He blinked until he could see again, and the only white-hot anything was the lantern in Mary’s hand.

“Did they find them, Mr. Epperson? Are they all right?”

“Yes to both questions, doctor. The Pinks were able to extract them. They were taken to a plantation in northern Alabama, not far from Fort Chattanooga. Right now they’re at a railroad stop at Lookout Mountain. Mr. Lincoln thought you’d want to know.”

“Thank you,” he said. Gideon did feel some relief, but not enough to wipe away the last of the lava-bright anger. He clenched his jaw, then unfastened it to say, “And I’ll thank him, too, when I see him. Will the Pinks bring them back to D.C.?”

“I don’t know. Mr. Pinkerton thought they’d be safer … well, if they were farther away from you, if you don’t mind me saying so. But he’s called in Kirby Troost, in case an escort to the North is called for.”

“Troost? How in God’s name did he find him?”

“No idea, Dr. Bardsley. But I hope that meets with your satisfaction.”

“Very much, yes. If we do need to move my family, he’s the man to do it.”

Rationally, Gideon knew the Pinkertons were right: Leaving them in place was probably the best strategy for now, though having Troost as a backup plan made him feel better about the whole thing. Let them stay close to their point of liberation while the pressure was on. Anyone in pursuit would assume they were running as far and as fast as possible, right back to the District of Columbia. Right back to Gideon, who’d always looked after them, hell, high water, or hunger.

But he knew his mother well—a simple woman who sometimes amazed him with her lack of curiosity, and sometimes annoyed him with her nervous nature. He knew of the safehouse in question, a quiet and hidden place at the edge of Lookout; he’d been there before, when he worked at the university. But all its quietness and all its hiddenness would never assuage her fears. She’d wear them like a blanket, and share them with her young charge. He thought unhappily of Caleb, a calm, quiet boy who’d been a toddler when they’d first come to the East Coast, and had grown into a solemn, silent thing that reached his uncle’s hips in height. The poor child would absorb his grandma’s fears, and hold them inside, and say nothing because that was how he’d made it this far.

Gideon sighed.

The best he could hope for was to protect them from each other. It was both the least he could do, and the most he could expect to accomplish. But these were not the best of times, and so far, he had not protected them from anything.

When there was nothing left to be done at the ruins of the Jefferson’s laboratory wing, Mary, Henry, and Gideon Bardsley climbed into Mary’s carriage and made the quick ride back to the Lincoln home. Once there, Mary left the two men in the library, where her husband was ensconced in his favorite chair with a blanket over his legs and a cup of coffee in his hand.

Thin, sallow Nelson Wellers sat in a chair across from the fire, and Polly stood by with the steaming pot, ready to dole out a warm beverage to the night-chilled newcomers.

“Gideon, Henry. Please come in. Take a seat,” the president urged. “Coffee, anyone?”

Henry politely waited while Polly served. When the maid finally pushed her little cart out of the room, he asked Lincoln, “So, the Pinkerton agent—she hasn’t arrived yet?”

Abraham Lincoln shook his head. “No, but any minute now, I should think.”

Gideon lifted an eyebrow as he dropped into a large leather chair. “She?”

“Oh, yes. One of their finest investigators, or so I am assured. An eminently capable woman,” he said. “But Henry’s told you of your mother, I hope? She and Caleb are safe and sound, and Troost is en route to them as we speak.”

“Yes, the marshal told me. They’re in Tennessee.”

“It’s less than ideal.” Lincoln spoke aloud what Gideon had privately concluded. “But it’s the best possible arrangement at this time. If they run, the bloodhounds will chase them, so I think we can all agree that they’re better off hiding until we know precisely what we’re up against. Now, Henry”—he shifted topics so smoothly, Gideon didn’t have time to offer some gentle agreement—“that telegram you sent was most alarming. I was hoping you could give us the particulars, and perhaps fill in some of the gaps between what we heard last week and your present understanding of the situation.”

“It might be best to wait for the Pinkerton agent. He’ll need—I mean, she’ll need—to be briefed, and she might have questions.”

A deep gong rang through the first floor, and Lincoln smiled. “A good suggestion, and good timing, too. I believe that’s her.”

Nelson Wellers reached one hand into his coat as if he did not share the former president’s confidence that this visitor was a fellow agent, not something more sinister; and Henry Epperson tensed as well. But within moments Polly returned. She was flushed, and glanced nervously between the newcomer and the men in the room.

“Gentlemen,” she said. “I … um. This is … this is Maria Boyd. She says she’s with the Pinkertons, and she showed me her badge … but…”

“But nothing,” Lincoln nodded reassuringly. “All’s well, Polly, thank you. Could you bring us another pot of coffee, please? Our guest might care for a cup. And, Miss Boyd—that’s your preferred address, isn’t it? Thank you for coming on such short notice.”

Stunned out of their usual manners, Nelson Wellers and Henry Epperson stayed in their seats for another awkward beat, then fumbled their coffee cups aside and rose as they recalled that standing was the usual protocol when a woman arrived. But Gideon Bardsley stayed where he was. He, too, was dumbfounded, but even once his shock passed, he had no intention of rising.

Maria Boyd, better known in the papers as “Belle Boyd,” was of average height, with posture that indicated good breeding. True to rumor, hers was the sort of body to launch a thousand ships: voluminous, shapely breasts and a narrow waist, graceful shoulders and a long, lean neck, but only the very kind or terribly nearsighted had ever described her plain, horselike face as “beautiful.”

She was no longer the hoopskirted coquette from the gossip pages. Now the notorious spy of yore wore something simple but more modern, a gray dress that was full only at the rear. Gideon was idly surprised to note that the Cleopatra of the Confederacy must have fallen on hard times—for he knew an oft-worn, insufficient article of clothing when he saw one; and her black cotton coat could not have been enough to keep her warm, even when augmented with a blue wool scarf that did nothing to mask the outstanding swell of her figure.

Calmly, deliberately, she unwound the scarf and unbuttoned her overcoat. “Gentlemen,” she greeted the lot of them, even catching Gideon’s eye in a pointed display of acknowledgment. “And Mr. President, of course,” she said to Lincoln. “‘Miss Boyd’ will be fine.”