Duke looked ill. His face waxen, he stared, then slowly shook his head. “But how did they know? I didn’t know you were in town.”

“Your friends are determined, and they have very long arms.” Tristan sank onto the chaise beside Leonora.

Jeremy closed the door. Deverell had returned to his position beside Charles. Crossing the room, Jeremy pulled out his chair from behind the desk and sat.

“Right.” Tristan exchanged glances with Charles and Deverell, then looked at Duke. “You’re in a serious and dire position. If you have any wits at all, you’ll answer the questions we put to you quickly, straightforwardly, and honestly. And, most importantly, accurately.” He paused, then went on, “We’re not interested in hearing your excuses—justifications would be wasted breath. But for understanding’s sake, what started you off on this tack?”

Duke’s dark eyes rested on Tristan’s face; from her position beside Tristan, Leonora could read their expression. All Duke’s violent bravado had deserted him; the only emotion now investing his eyes was fear.

He swallowed. “Newmarket. It was last year’s Autumn Carnival. I hadn’t before dealt with the London cent-per-cents, but there was this nag…I was certain…” He grimaced. “Anyway, I got in deep—deeper than I’ve ever been. And those sharks—they have thugs who act as collectors. I went up north, but they followed. And then I got the letter about A. J.’s discovery.”

“So you came to see me,” Jonathon put in.

Duke glanced at him, nodded. “When the collectors caught up with me a few days later, I told them about it—they made me write it all down and took it back to the cent-per-cent. I thought the promise would hold him for a while…” He glanced at Tristan. “That’s when things went from bad to hellish.”

He drew breath; his gaze fixed on Henrietta. “The cent-per-cent sold my vowels on, on the strength of the discovery.”

“To a foreign gentleman?” Tristan asked.

Duke nodded. “At first it seemed all right. He—the foreigner—encouraged me to get hold of the discovery. He told me how there was clearly no need to include the others”—Duke flushed—“Jonathon and the Carlings, as they hadn’t bothered about the discovery for all this time—”

“So you attempted by various means to get into Cedric Carling’s workshop, which by asking the servants you’d learned had been closed up since his death.”

Again Duke nodded.

“You didn’t think to check your aunt’s journals?”

Duke blinked. “No. I mean…well, she was a woman. She could only have been helping Carling. The final formula had to be in Carling’s books.”

Tristan glanced at Jeremy, who returned a wry look. “Very well,” Tristan continued. “So your new foreign backer encouraged you to find this formula.”

“Yes.” Duke shifted on the chair. “At first, it seemed quite a lark. A challenge to see if I could get the thing. He was even willing to underwrite buying the house.” His face clouded. “But things kept going wrong.”

“We can dispense with a list—we know most of it. I take it your foreign friend became more and more insistent?”

Duke shivered. His eyes, when they met Tristan’s, looked haunted. “I offered to find the money, buy back my debt, but he wouldn’t have it. He wanted the formula—he was willing to give me as much money as it took to get it, but it was get the damned thing for him—or die. He meant it!”

Tristan’s smile was cold. “Foreigners of his ilk generally do.” He paused, then asked, “What’s his name?”

What little color had returned to Duke’s face fled. A moment passed, then he moistened his lips. “He told me if I told anyone at all about him, he’d kill me.”

Tristan inclined his head, gently said, “And what do you imagine will happen to you if you don’t tell us about him?”

Duke stared, then glanced at Charles.

Who met his gaze. “Don’t you know the punishment for treason?”

A moment passed, then Deverell quietly added, “That’s assuming, of course, that you make it to the scaffold.” He shrugged. “What with all the ex-soldiers in the prisons these days…”

Eyes huge, Duke dragged in a breath and looked at Tristan. “I didn’t know it was treason!”

“I’m afraid what you’ve been doing definitely qualifies.”

Duke hauled in another breath, then blurted out, “But I don’t know his name.”

Tristan nodded, accepting. “How do you contact him?”

“I don’t! He set it up at the beginning—I have to meet him in St. James’s Park every third day and report what’s happened.”

The next meeting was to occur the following day.

Tristan, Charles, and Deverell grilled Duke for a further half hour, but learned little more. Duke was patently cooperating; recalling how keyed up—how panic-stricken, she now realized—he’d been earlier, Leonora suspected he’d realized that they were his only hope, that if he helped, he might escape a situation that had transformed into a nightmare.

Jonathon’s assessment had been accurate; Duke was a black sheep with few morals, a cowardly and violent bully, untrustworthy and worse, but he wasn’t a killer, and he’d never meant to be a traitor.

His reaction to Tristan’s questions about Miss Timmins was revealing. His face a ghastly hue, Duke falteringly recounted how he’d gone up to check on the ground-floor walls, heard a choking sound in the dimness, and looked up, to see the fragile old woman come tumbling down the stairs to land, dead, at his feet. His horror was unfeigned; it was he who had closed the old lady’s eyes.

Watching him, Leonora grimly concluded justice of a sort had been served; Duke would never forget what he’d seen, what he’d inadvertently caused.

Eventually, Charles and Deverell hauled Duke off to the club, there to be held in the basement under the watchful eyes of Biggs and Gasthorpe, together with the weasel and the four thugs Duke had hired to help with the excavations.

Tristan glanced at Jeremy. “Have you identified the final formula?”

Jeremy grinned. He picked up a sheet of paper. “I’d just copied it out. It was in A.J.’s journals, all neatly noted. Anyone could have found it.” He handed the sheet to Tristan. “It was definitely half Cedric’s work, but without A.J. and her records, it would have been the devil to piece together.”

“Yes, but will it work?” Jonathon asked. He’d remained silent throughout the interrogation, quietly taking things in. Tristan handed the paper to him; he scanned it.

“I’m no herbalist,” Jeremy said. “But if the results as laid out in your aunt’s journals are correct, then yes, their concoction will definitely aid clotting when applied to wounds.”

“And it was lying there in York for the past two years.” Tristan thought of the battlefield at Waterloo, then banished the vision. Turned to Leonora.

She met his eyes, squeezed his hand. “At least we have it now.”

“One thing I don’t understand,” Humphrey put in. “If this foreigner was so set on finding the formula, and he was able to order Jonathon here killed, why didn’t he come after the formula himself?” Humphrey raised his shaggy brows. “Mind you, I’m deuced glad he didn’t. Mountford was bad enough, but at least we survived him.”

“The answer’s one of those diplomatic niceties.” Tristan rose and resettled his coat. “If a foreigner from one of the embassies was implicated in an attack on, even the death of, an unknown young man or even two from the north, the government would frown, but largely ignore it. However, if the same foreigner was implicated in burglarly and violence in a house in a wealthy part of London, the house of distinguished men of letters, the government would assuredly be most displeased and not at all inclined to ignore anything.”

He glanced at them all, his smile coolly cynical. “An attack on property close to the government’s heart would create a diplomatic incident, so Duke was a necessary pawn.”

“So what now?” Leonora asked.

He hesitated, looking down into her eyes, then smiled faintly, just for her. “Now we—Charles, Deverell, and I—need to take this information to the proper quarters, and see what they want done.”

She stared at him. “Your erstwhile employer?”

He nodded. Straightened. “We’ll meet again here for breakfast if you’re agreeable and make whatever plans we need to make.”

“Yes, of course.” Leonora reached out and touched his hand in farewell.

Humphrey nodded magnanimously. “Until tomorrow.”

“Unfortunately, your meeting with your government contact will have to wait until morning.” Jeremy nodded at the clock on the mantelpiece. “It’s past ten.”

Tristan, heading for the door, turned, smiling, as he reached it. “Actually, no. The State never sleeps.”

The State for them meant Dalziel.

They sent word ahead; nevertheless, the three of them had to cool their heels in the spymaster’s anteroom for twenty minutes before the door opened, and Dalziel waved them in.

As they sank onto the three chairs set facing the desk, they glanced around, then met each other’s eyes. Nothing had changed.

Including Dalziel. He rounded the desk. He was dark-haired, dark-eyed and always dressed austerely. His age was unusually difficult to gauge; when he’d first started working through this office, Tristan had assumed Dalziel to be considerably his senior. Now…he was starting to wonder if there were all that many years between them. He had visibly aged; Dalziel had not.

As cool as ever, Dalziel sat behind the desk, facing them. “Now. Explain, if you please. From the beginning.”

Tristan did, severely editing his account as he went, leaving out much of Leonora’s involvement; Dalziel was known to disapprove of ladies dabbling in the game.