"This is your work, of course." It was merely something to say. She already knew the answer.

"The tunnel's structural y weak, here see those rotting bricks? You could scoop them out with a teaspoon."

Mary did see. "Is it safe to be here now?"

He shrugged. "It's unlikely to cave in tonight..."

"That's not very rea.s.suring."

He grinned. "I thought you enjoyed danger."

It was wiser to ignore that. "Was it just the structural weakness that made you block it off?"

"It's clearly not a drainage pipe. Doesn't appear on sewer maps. It's dry. And I don't like the idea of open dead-ends. Enough fools try to creep into the sewers, thinking they'l find their fortunes in here silver teaspoons and gold sovereigns, ripe for the picking. There's no sense in leaving them a hiding-place."

Mary nodded. "So until you began work, the tunnel was easily accessible from the main sewer."

"Yes. And is likely to have been that way since it was built."

They stared at each other in mutual perplexity. It simply didn't make sense. And without knowledge of when the tunnel had been built, they couldn't even begin to theorize about its original use or whether it might be in some way connected with Honoria Dalrymple's interest in it.

In that moment of silence, there came a mundane but entirely unexpected sound something that made Mary freeze, any further questions forgotten. It was a faint but definite cough. And it came from some distance away.

James's head snapped round. Clearly she'd not imagined it. He turned back and she nodded, replying to his unspoken question. Swiftly, silently, they shuttered their lanterns. It took a moment for their eyes to adjust to the dark. Yet it wasn't completely black somewhere, in the far recesses of the tunnel behind James, there was something other than inky darkness. It wasn't so much light as the possibility of it, a faint aura of yel owy il umination that had yet to reach them.

As Mary's eyes grew accustomed to the shadows and vague shapes, she felt James pivot to face the intruder. He, or she, was coming from the opposite direction. Further downstream, closer to the Thames. James took a slow, silent step, then another. There was no need to hurry the third party was making his way at a steady pace. They could hear his legs swishing through the water, the soles of his boots squeaking occasional y. As they drew closer Mary had no idea how far down the tunnel he was (a hundred yards? more? impossible to say when she'd no perspective, no knowledge of the tunnels) she began to hear a low vocal sound, too.

It was like a cross between wheezing and muttering beneath his breath.

James's hand b.u.mped against her elbow, signal ing her to stop. Not that she had a choice: his back fil ed her line of vision and she couldn't get round him without alerting their quarry. She could only wait for James to make his move.

The intruder splashed closer, his lantern's glow bobbing and growing stronger by the moment. His steps were measured, neither swift nor slow. They suggested that he was prepared for this adventure, knew what he was about neither a youngster larking about nor a casual opportunist. Mary clenched her lamp tighter, wishing it were something more substantial something more like a weapon.

From the way James gripped his lantern, it was clear he shared her thoughts.

The intruder rounded a final curve and final y they saw him directly: a golden dazzle of light, and a shadowy form behind that brightness. Middle height, middle breadth. Face shadowed by a deep-brimmed hat. Mary thought she glimpsed an expression of grim intent but then who wouldn't look that way, striding through a sewer on a dark February night? She squinted, trying to discern his features.

"Stop!" The voice was James's, loud and commanding, echoing off the bricks. With a swift gesture, he opened his dark lantern. The sudden burst of light dazzled her eyes, and she flinched despite herself. "State your name and business."

The man scarcely hesitated. But instead of speaking, he hurled his lantern straight into James's face. There was a crash of broken gla.s.s, a clatter of metal, a frantic splashing, al amplified by the hol ow tunnel. Al went dark.

"Are you hurt?" Mary dropped to her knees, tore off her huge, clumsy gloves. She'd seen James try to protect his face. Seen him drop his own lantern in the attempt. What were the chances of an explosion, with flame and grease in sudden, violent contact?

And if a fire caught now, in this long, narrow s.p.a.ce ... she stopped her train of thought. Her fingers met oilcloth, coa.r.s.e and slick over a broad, convulsing surface. His back. "Speak. Are you injured?"

"He's running away!"

"Are you burned?" She found his shoulders, tried to manoeuvre round to face him.

"No ouch! I don't think so."

"Sorry did I hurt you?"

"No. Chase him down, d.a.m.n it!"

Mary turned towards the sound of distant and fast-receding splashing. "Not 'til I'm satisfied you're al right. Besides, he's got a head start."

"And whose fault is that?"

Such irritability, she decided, was a sign of good health. "Fine. Don't do anything stupid while I'm gone." She retrieved her lantern and, moving as quickly as her oversize boots would al ow, set off down the tunnel. The water grew deeper as she went, pressing against the backs of her thighs, as though urging her on. She kept her lantern dark, her movements smooth. It was just possible that thinking himself safe, the intruder would stop. And then what? she wondered, but pushed on nevertheless.

She rounded a final curve and blinked with surprise. Here, the sewer gradual y broadened like a cone, and deepened, too: she was submerged nearly to her waist and the floor continued to drop away before her. She halted, uncertain, and now she heard a different sound from her quarry. The rapid splashing ceased. There came a sc.r.a.ping sound, and then a different sort of watery ripple. It was too dark to see she knew only that he wasn't within arm's reach and so she listened for a few moments longer. There was nothing she could make out simply through sound. She thought of James, in al probability bloodied and lacerated, oozing filth lapping at his wounds. She couldn't return without an explanation, could hardly swim on blindly, risking lantern and life. And so, steadying herself against the ceaseless flow of water, she opened her dark lantern with a swift, decisive snap.

Black water, swirling al about her.

Dark, rotting bricks, gleaming darkly above.

And, perhaps fifty yards ahead, a smal punt nosing its way Thames-ward, steered by a figure in dripping oilskins. He glanced back to the source of the light and caught sight of Mary. She couldn't make out his expression, but it seemed to her that he stared intently. There was no triumph or glee in his opportune escape.

For half a moment, she weighed the possibility of throwing her lantern into his boat. Regrettably, the ceiling was too low, the tunnel too narrow for her to throw such a distance with accuracy. She had to content herself, instead, with watching him glide through the currents, learning what she could. He punted with competence but lacked the economy of motion one customarily saw in river men. Only when he disappeared from sight did she begin the long trek up-sewer to James. She hoped that he'd fol owed her orders to do nothing stupid with more success than she had his.

They retraced their steps in grim silence. Despite his injuries, James insisted that Mary climb the ladder first, and the first thing she saw as she surfaced above ground was Barker's accusing face.

He sprang down from the driver's seat and, as she turned to give James a hand, he pushed her aside without ceremony or apology. "Lucky to be alive, sir," he said in a gruff tone, hauling James from the manhole with such swiftness that they both stumbled slightly.

"Don't be so melodramatic, Barker," said James, sounding quite his usual exasperated self. "And how d'you know we didn't just take a pleasant strol ?"

"Echoes, sir. Heard your voice hol ering, a way away."

"Wel , we're fine. That is, I'm fine. And Mary chased the vil ain down half a mile or so of sewer, so I presume she is, too." He swung round to look at her. "Isn't that right?"

She nodded. "You're bleeding."

"Where?" He raised his hand to his face, but she knocked it aside.

"Not with those filthy gloves," she said quietly. She turned to Barker. "I don't suppose you've anything like bandages and something to cleanse a wound."

To her surprise, he answered with something less than utter hostility. "There's a smal case beneath the rear-facing bench."

She was already shucking off the coat and waders, scrambling to smooth down her skirts in a semblance of modesty. Oh, who was she trying to fool? "Get in," she said to James. "No time to lose."

She opened the carriage door and motioned him inside.

"I'd make the most of this opportunity if I weren't covered in slime," he murmured, waggling his eyebrows in the fashion of a music-hal vil ain. Then he flinched. "Ouch. That's where I'm bleeding from, isn't it?"

She laughed. "Just get inside. We've things to discuss while I clean that disgusting gash."

His injuries were much less severe than they might have been: a jagged two-inch cut along his brow bone, and several smal er nicks. The thick flusher's gloves had served him wel there, too: if the lamp had shattered against his bare hands, he'd have been both burnt and badly lacerated. As it was, his injuries came only from tiny flying splinters of gla.s.s.

As Barker had said, she found a smal case containing bandages, clean compresses, scissors and even a pair of tweezers. Someone likely James had antic.i.p.ated the need for rudimentary medical care in unusual circ.u.mstances.

She picked four glittering shards from his cheeks and laid them careful y in a clean handkerchief. "This wil hurt," she warned, uncorking a flask of whisky.

"It's only fair; I did the same to you last year, in this very carriage."

She smiled at the memory. "In the middle of the night."

"Do you stil carry the marks?"

She showed him her hand, stil marked by Angelica Thorold's fingernail punctures. "A little. But don't worry: I daresay your scar wil look positively dashing."

He bore her very thorough cleansing and bandaging in silence, the only sign of pain a tightening of his jaw when the alcohol burned his raw flesh. "Any reason you're saving these?" he asked, pointing to the gla.s.s fragments.

His skin was very warm beneath her fingers, his breath soft against her cheek. She concentrated on wiping the cut clean. "Don't you want to know who that man was?"

"I did ask..."

"Yes, and look how wel that went."

"It was the reasonable thing to do," he protested.

"What would you have done attacked first and asked questions later?"

"Hold stil you're making the wound bleed again." She finished her work and selected the largest piece of broken gla.s.s, a rough triangle, fingernail-sized and somewhat tinged with red.

"Look."

"And?" he asked, with exaggerated patience.

She held it up to the carriage-lamp. "There. At the edge."

"I don't see what oh." The slight frown between his eyes suddenly deepened. "Is that etching?"

"Yes." Her eyes sparkled with excitement. "Instead of a dark lantern, he was carrying an oil lamp with etched gla.s.s. Quite an expensive item for a sewer robber, wouldn't you say?"

"Odd, certainly. It could be stolen goods, though.

He might even have pinched it himself."

"For the purpose, you mean? Lamps like this are expensive, even when they're sold as stolen goods.

And if you were going to the trouble to steal one yourself, wouldn't you choose a sensible one like a dark lantern?"

"What are you suggesting, Mary?"

"I think our intruder is no ordinary opportunist. As you pointed out, he'd have to learn the tide tables, and have special waterproof clothing. But he didn't have the right sort of lantern I'd argue that he simply took the nearest item to hand."

"So he's middle-cla.s.s, at least."

"Or more. He'd a punt waiting it was clearly an organized attempt to navigate the sewers. And his punting style may be significant: he certainly wasn't good enough to be a river man."

"That stil leaves the greater part of the population of London."

Mary chafed at this scepticism. There was something ... a feeling ... a detail she couldn't manage to identify that formed the core of her certainty. She closed her eyes and brought to mind the image of the man, floating down the sewer into the open river. Watchful. Thwarted. Learning from this incident. And suddenly she had it. "It's his bearing he was so focused and disciplined.

Almost military in his posture."

James snorted. "A renegade army officer storming the Palace?"

Mary remained in earnest. "Is there a rule against criminals being affluent? Or perhaps he's not a criminal at al ; maybe his intentions were general y harmless, and he simply panicked when confronted."

"Mmm. I suppose a patrician sewer-invader is more likely to be connected with your lady-in-waiting ... what's her name?"

"Honoria Dalrymple. The Honourable."

His lips twitched. "The Honourable Honoria?"

"Clearly her parents weren't thinking."

"Right. So you are imagining two high-born sewer rats one of whom may be responsible for al this?

But what for?"

She sighed. "No idea. But one of them isn't imaginary."

"In that case, we'd better focus on her."

She met his gaze, startled. "'We'?"

He offered her his most winning smile. "Say no, if you like."

The precious seconds ticked by as she struggled.

She couldn't.

Mustn't.

Oughtn't.

And yet, it made sense. He had legitimate access to the sewers. He was an intel igent, entirely trustworthy partner. And there was a sense of inevitability to this newest partnership. It always seemed to come down to James. This case, which had begun so dul y, was fast becoming most complex for her personal y, at least.

His grin turned smug. "Thought so. Now, tel me al about the Honourable Honoria."

Eighteen.