“We assume his controllers wanted his last day in London to be as normal as possible,” Seymour said.

Gabriel found the explanation dubious at best. He entered the bathroom and opened the medicine cabinet. Scattered among the various lotions, creams, and grooming devices were three bottles of prescription medication: one for sleep, one for anxiety, and one for migraine headaches.

“Who prescribed these?”

“A doctor who works for us.”

“Grigori never struck me as the anxious type.”

“He said it was the pressure of writing a book on deadline.”

Gabriel removed a bottle of indigestion medication and turned the label toward Seymour.

“He had a fickle stomach,” Seymour said.

“He should have eaten something other than salted herring and pasta sauce.”

Gabriel closed the cabinet and lifted the lid of the hamper. It was empty.

“Where’s his dirty laundry?”

“He dropped it off the afternoon he vanished.”

“That’s exactly what I would do if I were preparing to redefect.”

Gabriel switched off the bathroom lights and followed Seymour down a flight of steps to the sitting room. The coffee table was scattered with newspapers, a few from London, the rest from Russia: Izvestia, Kommersant, Komsomolskaya Pravda, Moskovskaya Gazeta. On one corner of the table stood a Russian-style tea glass, its contents long evaporated. Next to the glass was another ashtray filled with cigarette butts. Gabriel picked through them with the tip of a pen. They were all the same: Sobranie White Russians. Just then, he heard the sound of laughter outside in the mews. Parting the blinds in the front window, he watched a pair of lovers pass arm in arm beneath his feet.

“I assume you have a camera somewhere in the courtyard?”

Seymour pointed to a downspout near the passageway.

“Any Russians dropping by for a peek?”

“No one that we’ve been able to link to the local rezidentura.”

Rezidentura was the word used by the SVR, the Russian foreign intelligence service, to describe their operations inside local embassies. The rezident was the station chief, the rezidentura the station itself. It was a holdover from the days of the KGB. Most things about the SVR were.

“What happens when someone comes into the mews?”

“If they live here, nothing happens. If we don’t recognize them, they get a tail and a background check. Thus far, everyone’s checked out.”

“And no one’s tried to enter the cottage itself?”

Seymour shook his head. Gabriel released the blinds and walked over to Grigori’s cluttered desk. In the center was a darkened notebook computer. Next to the computer was a telephone with a built-in answering machine. A red message light blinked softly.

“Those must be new,” Seymour said.

“Do you mind?”

Without waiting for a response, Gabriel reached down and pressed the PLAYBACK button. A high-pitched tone sounded, then a robotic male voice announced there were three new messages. The first was from Sparkle Clean Laundry and Dry-Cleaning, requesting that Mr. Bulganov collect his belongings. The second was from a producer at the BBC’s Panorama program who wished to book Mr. Bulganov for an upcoming documentary on the resurgence of Russia.

The last message was from a woman who spoke with a pronounced Russian accent. Her voice had the quality of a minor scale. C minor, thought Gabriel. Key of concentration in solemnity. Key of philosophical introspection. The woman said she had just finished reading the newest pages of the manuscript and wished to discuss them at Grigori’s convenience. She left no call-back number, nor did she mention her name. For Gabriel, it wasn’t necessary. The sound of her voice had been echoing in his memory from the moment of their first encounter. How do you do, she had said that evening in Moscow. My name is Olga Sukhova.

“I suppose we now know who wrote those notes in Grigori’s manuscript.”

“I suppose we do.”

“I want to see her, Graham.”

“I’m afraid that’s not going to be possible.” Seymour switched off the answering machine. “Rome has spoken. The case is closed.”

THE BLOCKS of council flats looming over Delamere Terrace looked like something the Soviets might have thrown up during the halcyon days of “developed Socialism.” Artlessly designed and poorly constructed, each building bore a very English-sounding name suggesting a peaceful countryside existence within, along with a yellow sign warning that the area was under continuous surveillance. Grigori had walked past the flats a few minutes before his disappearance. Gabriel, retracing the Russian’s steps, did so now. Though he hated to admit it, Seymour’s briefing had shaken his absolute faith in Grigori’s innocence. Did he redefect? Or was he abducted? Gabriel was certain the answer could be found here, on the streets of Maida Vale.

Show me how they did it, Grigori. Show me how they got you into that car.

He walked to Browning’s Pool and stood outside the Waterside Café, now closed and shuttered. In his mind, he replayed the video. At precisely 18:03:37, it appeared Grigori had taken note of a couple crossing Westbourne Terrace Road Bridge from Blom field Road. The man was wearing a belted raincoat and a waxed hat and holding an open umbrella in his left hand. The woman was pressed affectionately to his shoulder. She wore a woolen coat with a fur collar and was reading something-a street map, thought Gabriel, or perhaps a guidebook of some sort.

Gabriel turned now, as Grigori had turned, and walked along the edge of Browning’s Pool to the steps leading to Warwick Crescent. At the top of the steps he paused, as Grigori had paused, though he lit no cigarette. Instead, he made his way to Harrow Road, where Grigori had seen something-or someone-that made him quicken his pace. Gabriel did the same and continued on along the empty pavements for another two hundred meters.

Despite the hour, traffic along the busy four-lane thorough-fare was still thunderous. He stopped briefly near St. Mary’s Church, walked a few paces farther, and stopped again. It was here, he thought. This was the spot where Grigori had become too frightened to continue. The spot where he had frozen in his tracks and turned impulsively toward the oncoming traffic. In the recording, it had appeared as if Grigori had briefly considered attempting to cross the busy road. Then, as now, it almost certainly would have meant death by other means.

Gabriel looked to his left and saw a brick wall, six feet tall and covered in graffiti. Then he looked to his right and saw the river of steel and glass flowing along Harrow Road. Why did he stop here? And why, when a car appeared without being summoned, did he get in without hesitation? Was it a prearranged bolt-hole? Or a perfectly sprung trap?

Help me, Grigori. Did they send an old enemy to frighten you into coming home? Or did they send a friend to take you gently by the hand?

Gabriel gazed into the glare of the oncoming headlamps. And for an instant he glimpsed a small, well-dressed figure advancing toward him along the pavement, tapping his umbrella. Then he saw the woman. A woman in a car-length leather coat who carried no umbrella. A woman who was hatless in the rain. She brushed past him now, as if late for an appointment, and hurried off along Harrow Road. Gabriel tried to recall the features of her face but could not. They were ghostlike and fragmentary, like the first faint lines of an unfinished sketch. And so he stood there alone, London’s rush hour roaring in his ears, and watched her disappear into the darkness.