We came to a halt, wings still quivering, ten feet from the hedgerow at the field's end.

Javitz peeled one hand off the control stick and cut the fuel.

Silence pounded at our eardrums. In a calm voice that sounded very far away, Javitz said, “I'm going to go get drunk now, if you don't mind. I'll meet you back here at dawn.”

“What-” I strangled on the word, cleared my throat and tried again. “What about the machine?”

“I'll make arrangements.”

The arrangements came from the nearby house to meet us, in the form of a grizzled farmer and his strapping young son, the latter of whom was clearly the enthusiast. The lad stared from the aeroplane to the pilot in open admiration, while his disapproving father moved to tie our eager machine down to earth. I half-fell down the ladder, accepted the valise that Javitz thrust into my arms, and watched him march away down the field with the young man trailing behind, pelting him with unanswered questions.

After a minute, I realized an older man was standing at my side, and had asked me something. “Terribly sorry,” I said. “I could rather use a Ladies', if you might direct me?”

I felt his hand on my elbow, propelling me in the direction of the building he'd come out of. He led me through a kitchen, showed me a door, and went away. I put down the valise, closed the door, and knelt to vomit into the tidy enamel lavatory.

When the spasm had passed, I stayed where I was for a time, shuddering with a combination of cold and reaction, emitting a noise that was part groan and part cry. Not unlike the noise the wind had made all afternoon around my head.

All right, I said after a minute. Enough. I got to my feet, washed my hands, splashed water on my face, and even went into my valise for a comb to restore my hair to order. When I came out, I felt approximately halfway to human.

Which was just as well: The man standing in the farmer's kitchen was so out of place, he could only be Mycroft's Inverness contact, colleague to Mr MacDougall.

“Mungo Clarty, at your service,” he declared. His name and speech patterns were Scots, although the accent originated two hundred miles to the south. He marched across the room with his hand extended, pumping my arm as if trying to draw water. “I've been instructed to make you welcome and get whatever you might want. And if you're fretting over your pilot, I've sent a friend to look after him, in case he decides to get a bit the worse for wear. I've telephoned to a dear friend of mine, runs a lovely boarding-house in the town with more hot water than you could ask for, beds fit for a queen and a cellar second to none. Does that sound like what you'll be needing?”

Had he remained where he was, I might have draped myself around him in gratitude and wept on his shoulder, but he had let go of my hand and picked up my valise, and was already taking our leave from the farmer, leading me from the warm kitchen to his waiting motor, talking over his shoulder all the time.

“You haven't had any information from MacDougall?” I asked when he paused for breath. His motorcar was not as warm as the farmer's kitchen, but it was blessedly out of the wind, and the travelling rug he tucked over my knees was thick.

“He said to tell you the waiter had gone to see his mother, whatever that means, but that he's going after him.”

I took a breath, and pushed away temptation. “Good man. I need to visit all the hotels and restaurants in town.”

“All the-that'll take most of the night!”

“What, in a town this size?”

“ Inverness is the door to the north,” he said, sounding reproachful. “Anyone going to northern Scotland passes through here.”

“Superb,” I muttered. “Perhaps we should begin with any ticket agencies that may be open.”

It was, as Clarty had warned me, many hours before I took to that bed fit for a queen. Even when I did, so cold through that I gasped with relief at the hot-water bottle against my feet, the physical warmth had no chance against the turmoil of my thoughts.

We had found no trace of them. I had looked at my last pair of the photographs Holmes had left me, loath to let go of them, but in the end decided that, from here on, the places I would be asking were so remote, any three strangers would attract notice: descriptions would suffice. I left the photographs with Clarty, so he could repeat the circuit of ticket agents and hotels during the daylight hours.

Friday morning, at dawn, I returned to the air field to do it all again.

If Inverness was a tenth the size of Edinburgh, Thurso would have a tenth the population of Inverness, too small a setting for Mycroft to have any sort of an agent: From here on, I was on my own. I had asked for a car to pick me up well before dawn, not wanting to rob Clarty of his already short sleep, and I could hear its engine chuckling on the street outside when I walked down the stairs of the boarding-house, so ill-slept I felt hung over.

The owner was there, looking fresh as a terrier, and greeted me a good morning.

“I don't suppose you had any messages during the night, for me?” I asked her.

But she had not had a message to assure me that Holmes had resolved the issue on his own. Nothing to transform my Valkyrie ride through hell into a placid, unadventurous, puffing, ground-based train-ride back to the warm, dry, August-kissed South Downs. I would even process the honey from the other hives, I pledged, were it to absolve me from climbing back into that aeroplane.

But, no message, telegraphic, telephonic, or even telepathic.

I followed the obscenely cheerful driver out onto the rain-shined street, and he drove me to the hay-field.

Javitz was there before me, his young admirer lingering at a distance. My pilot looked no better than I felt. Still, his hands were steady as he poured me a cup from a thermal flask filled with scalding coffee.

He walked away and finished his check of our various levels by torch-light. I cradled the coffee to its dregs, and dropped the cup back onto the flask. When he came back, I handed it to him, and glanced up at the glass-wrapped passenger chamber with loathing.

Instead of offering me a hand, as he had before, he leant back against the wing and lit a cigarette. “It's ninety miles, more or less, to Thurso,” he began. “That weather report you saw me with, back in London, warned me that the wind was building, and it's out of the north-east. That's why we came across the mountains from Edinburgh instead of following the coast-line.

“But from here on, we don't have a choice. Even if we keep inland, we'll get the wind. The weather's going to be bad,” he said bluntly. “It's expected to blow itself out by tomorrow, but today's going to be rough. And when we leave Thurso, it'll be worse.” He studied me in the half-light. “This could kill us.”

Since I had come to work with Holmes, I had spent rather more time than most women my age in contemplating my imminent death. Gun, knife, bomb-I had faced all those and survived. Death by fire would be terrible, and drowning awful, but relatively quick. Falling from a great height, however, with no control, no hope, no avoiding the knowledge of a terrible meeting with the earth: That would be forever.

I swallowed: It would be easier, if I only knew. If I were certain that we were on the right track, that my presence in Orkney was the only hope for Damian and his Estelle, I would not hesitate to risk my life, or that of this brave man who had blindly done all I asked, and more. If I were sure…

I met his eyes. “I can't lie to you. There is a good chance that we are chasing a wild goose. We may get to Orkney and find our quarry has never been there, never had any intention of going there. And before you ask, yes, I knew it before we left London. My partner and his brother both disagree with me, and are hunting elsewhere.