"So no one cared anymore," I said.

"Possibly."

"But the seeds went somewhere for safekeeping," I said. "Or Kevin believed they did."

"And that is the riddle, isn't it? Or perhaps the treasure hunt." Zara pulled out her phone and did some scrolling as she walked over to the cash register counter.

The treasure hunt. Kevin had used those same words to describe his search for the seeds that last day at the Tidal Basin. Was that what I'd gotten involved in, along with someone else? A race to find hidden treasure?

Zara scribbled something on a piece of paper and held it out to me. "Please don't tell Alastair you got this from me. Better he thinks Kevin gave it to you. I suggest e-mailing him first rather than ringing him. Don't worry, he'll be in touch."

"Thank you." I tucked the paper in my camera bag.

She walked me to the door. "I presume, since you knew Kevin so well, you heard about his sister?"

She saw my blank expression. "Ah, apparently not. Well, I believe it's relevant to what brought Kevin here, his sense of urgency."

"Please go on."

"Both his parents died of Alzheimer's disease," she said. "His sister, who was two years younger than Kevin, was recently diagnosed with early-onset Alzheimer's." My shock must have shown, because she added, "I think that made him even more desperate to find those seeds, because of the apparent potent memory-enhancing property the lewisia plant supposedly possessed. Obviously it's an utter long shot as to whether any seeds could be germinated, but when one is desperate and a beloved sister is going to slowly lose her memory, one will do anything in one's power to prevent it, you know?"

I thought about Chappy. "Yes, I know."

"Kevin was making some discreet inquiries amongst contacts in the pharmaceutical industry to find out about Alzheimer's drugs that were being developed, whether there was any possibility of his sister taking part in tests for the most hopeful possibilities." She held the front door for me. "He even asked about water hyssop. Good luck, Sophie. I hope you find what you're looking for. And do be careful. Someone was here recently talking to Will, another American, who seemed especially interested in Hyssopus officinalis, as you were. I didn't think anything of it until just now."

I froze. "An American? Was it a man or woman?"

"A man."

"Could you describe him?"

"I'm afraid not. I was in my office and happened to see the two of them together out the window, but their backs were to me. And the gentleman left through the gate on Swan Walk. I asked Will why he let him in when we were closed, and he said the chap was particularly keen to see the garden as he was only in town for a day or two. He managed to talk Will into giving him a tour since he'd come all the way from America."

"Good Lord," I said. "I wonder if his visit had anything to do with Kevin's book. Though who else could have known about the plant?"

"I thought no one knew about it except Kevin, Alastair, and me," she said. "It is possible his visit was just a coincidence."

I said goodbye and walked down Royal Hospital Road toward Sloane Square. But I didn't think the visit of another American to the Chelsea Physic Garden asking about the same plant I did was a coincidence.

Sloane Square was nearly deserted at six o'clock on a chilly Sunday evening. I walked the last half block from Lower Sloane Street to the Underground station entrance thinking about everything Zara Remington had said.

"h.e.l.lo? Sophie?"

Will Tennant waved an arm over his head, signaling me from the fountain in the square across the street. A double-decker bus pulled away from a stop and cut off my view of him. When it pa.s.sed, he ran across the street and joined me.

"I thought I recognized you," he said in a cheerful voice. "Have you just come from the garden?"

"I have. Were you waiting for me?"

He gave an odd laugh. "No, I've just been round to tea with a friend down the King's Road and happened to spot you. How was your visit with Zara?"

"Fine," I said. "Apparently I'm not the only American to drop by the garden before it opens in the spring. Zara mentioned you were talking to one of my countrymen the other day."

He blinked. "Did she, now?"

"Could you describe him?"

"May I ask why?"

I patted my camera bag. "I'm a photographer on a.s.signment for a magazine. It's freelance. But I've got this compet.i.tor, you see. I think we're working on the same story. I was just wondering if it was the guy."

"What does he look like?" He gave me his off-kilter look. "Maybe I can tell you if it seems like the same chap."

"Uh . . . pretty average. In his forties, dark hair, blue eyes. A little overweight." If I made up a description, maybe he would contradict me and tell me what I wanted to know.

He shook his head. "You're in luck. This fellow was old, white hair, gla.s.ses. A bit stooped. Visiting from . . . what's that state? Missouri, I think he said. From Lincoln."

"Lincoln is in Nebraska."

Will looked surprised, but he grinned. "I guess I got it wrong. Are you walking to the Underground?"

"Yes."

"Me, too."

My pa.s.s had expired, so he waited while I bought a new one. "If you're going to be here for a while, you ought to get an Oyster Card," he said. "You can keep topping it off and it usually works out to be a cheaper deal if you pay by the week. You can use it on the buses, too."

"I know. I used to live here."

"Did you now?" At the bottom of the stairs he asked which way I was going.

"Victoria," I said.

"I'm off to Notting Hill Gate. The opposite direction. Are you staying around Victoria?"

"No," I said. "Mayfair. Here's my train. I'd better go. Goodbye, Will."

The train wasn't crowded, and when I boarded, I looked out the window at the platform. Will Tennant was gone. A moment later the bells chimed and we were advised to stand clear of the closing doors. The train left the station and I knew he'd seen right through my con and had lied to me.

What I wondered was, why?

13.

Harry was asleep in the adjoining room when I got back to the Connaught shortly after six, so James brought me a gla.s.s of sherry on a silver tray while I checked my e-mail. Nothing from Nick, which surprised me. We almost never went this long without being in touch. I wrote him a quick note and told him about my day in London, though I left out the details of my meeting with Zara Remington, and said I missed him like crazy, especially here. Then I drafted a vague e-mail to Alastair Innes explaining that I was a friend of Kevin's and was interested in visiting the Seed Bank while I was in London.

Afterward I went to the website of the Royal Botanic Gardens at Kew and clicked on the link to the Millennium Seed Bank. The more I read, the more I wondered why I had never heard of this place before, an enormous underground storage vault staffed by scientists and conservationists like Kevin who were racing against the clock to save thousands of plant species worldwide-by their account, sixty to one hundred thousand-that faced extinction. So far they'd collected eleven percent of the world's plants. Now they were aiming for one-quarter of all plants found on earth, specifically the ones threatened by extinction, as well as plants that might be useful in the future.

What struck me most was the urgency of their mission. It seemed as if this particular group of scientists had more inside knowledge than the rest of us about a giant doomsday clock that really was ticking down somewhere, an awareness that there wasn't much time to finish their work, or maybe even that there wasn't enough time. Harry knocked on my door just then, and I closed my laptop before he could see my computer screen.

"How about a drink?" he said, smiling. "The Coburg Bar serves some first-rate Scotch, plus they've got a drinks list that goes back before 1800. What do you say?"

"I say it sounds terrific."

As we finished our c.o.c.ktails by the fireplace-Harry had his Scotch, a sixteen-year-old Lagavulin, and I had a Pimm's Cup purely because it was considered the first English c.o.c.ktail-my phone buzzed in the pocket of my jacket. I pulled it out as we left the bar to walk down the street to Scott's. Alastair Innes had answered me as swiftly as Ryan Velis and Zara Remington had done.

Dear Ms. Medina, If you are available, I can meet you tomorrow, Monday, at 10 o'clock here at the Seed Bank. It is an easy trip from London; trains run regularly to Haywards Heath from Victoria Station and then I suggest you take a taxi to Wakehurst as the bus only runs once every two hours. I look forward to hearing from you. Brother Kevin's death was a huge shock to us all; I trust you and l will have much to discuss about a mutual friend who was beloved here by all who knew him. Yours sincerely, Alastair Innes "Everything all right, honey?" Harry asked. "You've been kind of quiet all evening. Something bothering you?"

I looked up from my phone. "Just a little jet-lagged is all. Everything's great. I'm sorry, do you mind if I answer this e-mail? I'm trying to get together with someone tomorrow. It'll only take a second."

"Go right ahead. I'm glad you'll be busy when I'll be in Lingfield. Who are you seeing, if you don't mind my asking? One of your old friends?"

"Actually, an old friend of Kevin Boyle's."

Harry looked surprised. "A Franciscan?"

"No, someone involved in conservation. A scientist." I slipped my arm through his. "Tell me about your lunch in Covent Garden. Did you have a good time?"

Harry let me change the subject and evade his questions for the second time in the past twenty-four hours, but sooner or later he was going to ask what was going on. I had no idea how much I would tell him, just as I had no idea how I was going to bring up the lewisia plant with Alastair Innes tomorrow.

But with jet lag stealing over me-that much was true-and Harry plying me with wine and good food in the coc.o.o.ned coziness of Scott's, I was feeling drowsy and light-headed, in no condition to think about any of that right now. I'd figure it out tomorrow when I had to.

I always did.

Harry and I ate breakfast in the Connaught's pretty gla.s.s-enclosed conservatory overlooking Mount Street the next morning before his friend's driver picked him up in a dark blue Jaguar to take him to Lingfield.

He kissed me goodbye in front of the crackling fire in the lobby fireplace. "There's a champagne reception and a dinner after the race, so I'll probably be back quite late. Don't feel like you need to wait up."

I laughed. "You party hard, Harry. I can't keep up with you."

He grinned. "Don't tell your mother. She'd tie me to a chair if she knew. Ever since my surgery she treats me like I'm made of gla.s.s. She's always telling me not to overdo it."

Truth to tell, his mild heart attack a year ago and a double-bypa.s.s operation before Christmas had scared me, too. But I'm like Harry. When I die, I hope my regrets-if I have any-are for things I've done, not what I wish I'd done.

"Have fun," I said.

"I love you, kitten."

"I love you, too. See you when you get back."

After the Jaguar pulled out of Carlos Place, I walked to the Bond Street Underground station and took two trains to Victoria, catching a Southern Railways train to Haywards Heath that pulled out of the station thirty seconds after I stepped on board. Perry sent me a text message as the train left London and crossed over the Thames.

Are we still on for lunch at 1? How about the Old Red Cow? Meet at the bureau first?

The Old Red Cow was a pub near Smithfield Market and it wasn't far from the International Press Service bureau. It was one of our favorite places for lunch or a pint at the end of the day.

I wrote him back: Absolutely on for lunch. I've got an appointment this morning but I'll be back by 1. Probably better to meet at the pub.

As soon as I hit Send, I regretted my choice of words. Perry doesn't miss a thing. He wrote back instantly.

Back from where? You out of town?

Long story. I'll explain when I see you.

Then I put my phone away so I could duck further questions.

The rest of the journey was uneventful and I had the carriage to myself for the forty-five-minute trip, except for a young man who came through with the tea trolley and the conductor who collected my ticket.

Haywards Heath was approximately forty miles due south of London, as Zara had said, and if you continued south for another twenty miles beyond that, you'd hit the English Channel and the seaside town of Brighton. By the time we pa.s.sed Gatwick Airport, the scenery had become mostly rural, black skeletal trees against a cold white sky, a somber-looking landscape of fields, and the occasional house in subdued tones of dull brown and washed-out green.

As Alastair Innes had promised, there was a taxi rank just outside the little station, which was built into a hillside and surrounded by woods. My cabdriver was from Afghanistan, and once he learned I'd visited his country, he spent the entire twenty-minute journey quizzing me about my work with International Press Service. As he turned into the private road for Wakehurst Place, he said over his shoulder, "You going to the mansion, miss?"

"No," I said. "The Seed Bank."

It was situated in a low-lying field, two industrial-looking metal structures like bunkers joined by a gla.s.s-vaulted roof. The building blended in with the greenish-yellow late-winter landscape, which was probably the point of its un.o.btrusive design. I went inside through the main entrance and gave my name to a young woman sitting behind a desk in a small waiting room.

"I'll ring Dr. Innes," she said after I'd signed in. "Please have a seat."

The room was as plain and unadorned as the exterior of the building except for a set of arty photographs behind the reception desk that I knew had to be seeds. Besides the front entrance, there were two other doors, both bright yellow and both closed, with pads to swipe ID badges next to them. I leafed through brochures about the Seed Bank and a colorful newsletter filled with pictures and articles about its latest projects until a pet.i.te, attractive woman in what looked like a hand-knitted Fair Isle cardigan, white blouse, and gray wool trousers opened the door nearest to where I was sitting.

"Ms. Medina?" she said. "I'm Fiona Eccleston. Dr. Innes has asked me to take you downstairs to the library whilst he finishes up with a meeting. He thought you might enjoy reading some information I've prepared for you about the Seed Bank."

I stood up. "That's very kind. Thank you."

She swiped her ID on the gray pad and, as we stepped into a corridor, the door closed behind us with a firm click. I hadn't considered there would be this much security in a place that stored seeds.

"We'll take the lift to the lower level," she said. "Follow me."

We walked through a quiet corridor and took the elevator down one level. The industrial-looking library was busier than I'd expected, and many of the tables were filled with people working on computers. A few of them glanced up when Fiona and I entered the room. She led me to a long table at the back of the room where a coffee-table book lay open next to a file folder. Inside the folder were several photocopied articles.

"These will give you an overview of our work here," she said. "Any questions, feel free to ask. And I'm sure Dr. Innes will be happy to answer anything I can't help you with."

A couple of heads snapped up at the mention of Alastair Innes and then it was eyes down. I thanked Fiona again and started flipping through the material she had put out for me. Besides the quiet clicking of computer keyboards and muted voices from nearby rooms, I heard a pervasive low hum, like an engine or perhaps a generator. When the phone rang a few minutes later, I heard Fiona say, "Of course, Alastair. I'll bring her right up."

I stood and she turned around. "Ms. Medina, Dr. Innes is free now. I'll walk you to his office."

I picked up my camera bag and followed her back to the elevator. It seemed we were retracing our steps to the reception area, but then Fiona turned down a hallway of closed doors that was as silent as a graveyard. The humming sound was less distinct here. She knocked on a door midway down the corridor.