“We checked it out. They fit.”

“Put the money inside now.”

Carter frowned. “I don’t know about you, Gabriel, but I never leave my wallet in the car, let alone thirty million in cash.”

“At this moment the embassy is surrounded by a hundred Metropolitan Police officers,” Gabriel said. “No one is going to break into the car.”

Carter nodded at the DS agents, and a moment later the bags were gone.

“You, too, Adrian. I’d like to have a word with the ambassador alone.”

Carter opened his mouth as though he were about to object, then thought better of it. “I’ll be down in the ops center,” he said. “Don’t be late, Gabriel. The show can’t start without you.”

Precisely what was said between Gabriel Allon and Ambassador Robert Halton never became known and was not included in any record of the affair, overt or secret. Their conversation was brief, no more than a minute in duration, and the DS agent standing guard outside the ambassador’s office later described Gabriel as looking damp-eyed but determined as he emerged and made his way toward the ops center. This time the kidnappers did not make him wait. The call, according to the clock above John O’Donnell’s workstation, came at 20:00:14. Gabriel reached for it instantly, though he remembered thinking as he did so that he would be happy never to speak into a telephone again for as long as he lived. His greeting was calm and somewhat vague; his demeanor, as he listened to the instructions, was that of a traffic officer recording the details of a minor accident. He posed no questions, and his face registered no emotion other than profound irritation. At 20:00:57, he was heard to murmur: “I’ll be there.” Then he stood and pulled on his coat. This time Carter made no attempt to stop him as he started toward the stairs.

He paused for a moment in the ground-floor atrium to slip on his miniature earpiece and throat microphone, then nodded silently to the Marine guard as he exited the embassy grounds through the North Gate. Carter’s Vauxhall sedan was parked in a flagrantly illegal space on the corner of North Audley Street. The keys resided in Gabriel’s coat pocket, along with a GPS beacon the size of a five-pence coin. He opened the trunk and quickly inspected the cargo before adhering the beacon near the driver’s-side taillight. Then he climbed behind the wheel and started the engine. A moment later he was turning into Oxford Street and marveling at the crush of last minute shoppers. Carter’s watchers followed him as far as Albany Street, where they photographed him making a left turn and heading north. That would be their last contact with him. As far as the Americans and British were concerned, Gabriel had now disappeared from radar.

That was not the case, however, at the Israeli embassy in South Kensington, where, in one of the more bizarre coincidences of the entire affair, a group of well-meaning Christians had chosen that night to conduct a candlelight vigil calling for peace in the Holy Land. Inside the building, Ari Shamron and Uzi Navot were holding a vigil of their own. Their thoughts were not of peace or the holidays or even of home. They were huddled round a smoky table in the makeshift operations room, moving their forces into place, and watching a winking green light heading along the eastern fringe of Regent’s Park toward Hampstead.

H e parked where they told him to park, in the Constantine Road at the southern tip of Hampstead Heath. There was no other traffic moving in the street, and Gabriel, as he had made his final approach, detected no signs of surveillance, opposition or friendly. He shut off the engine and pressed the interior trunk release, then opened the center console hatch and dropped the keys inside. A gentle rain had started to fall. As he stepped outside, he cursed himself for failing to bring a hat.

He walked to the back of the car and removed the first duffel. As he was reaching for the second, he heard noises at his back and wheeled around to find a pack of young carolers advancing festively toward him. For a mad instant he wondered whether they might be the Sphinx’s watchers but quickly dismissed that notion as they bade him a Happy Christmas and paraded obliviously by. He placed the second bag in the street and closed the trunk. The carolers were now singing “O Come, All Ye Faithful” outside a small brick cottage strung with holiday lights. A sign in the window read: GIVE US PEACE IN OUR TIME.

Gabriel towed the duffel bags a few yards along the street, then crossed a footbridge over a set of sunken railroad tracks and entered the heath. To his right was a darkened running track. In the cement esplanade outside the padlocked gate, four immigrant men in their twenties were kicking a football about beneath the amber glow of a sodium lamp. They appeared to pay Gabriel no heed as he labored past and started up the slope of Parliament Hill, toward the bench where they had told him to wait for their next contact. He arrived to find it occupied by a small man with a frayed coat and matted beard. His accent, when he spoke to Gabriel, was East London and leaden with drink.

“Happy Christmas, mate. What can I do for you?”

“You can get off the bench.”

“It’s my bench tonight.”

“Not anymore,” said Gabriel. “Move.”

“Piss off.”

Gabriel drew Adrian Carter’s Browning Hi-Power and leveled it at the man’s head. “Get the fuck out of here and forget you ever saw me. Do you understand?”

“Loud and fucking clear.”

The man got quickly to his feet and melted into the darkness of the Heath. Gabriel ran his hand along the back and underside of the bench and found a mobile phone taped to the bottom of the seat on the left side. He quickly removed the battery and searched the phone for any concealed explosive charges. Then he reconnected the battery and pressed the POWER button. When the telephone was back online, he spoke quietly into his throat microphone.

“Nokia E50.”

“Number?” asked Uzi Navot.

Gabriel recited it.

“Any recent activity.”

“It’s clean.”

“Text activity?”

“Nothing.”

Gabriel stared down at the lights of London and waited for the phone to ring. Fifteen minutes later, he heard a thin, tinny version of the Adhan , the Muslim call to prayer. He silenced it with a press of a button and raised the phone to his ear. It took them only thirty seconds to deliver the next set of instructions. Gabriel dropped the phone into the rubbish bin next to the bench, then took hold of the duffel bags and started walking.

At the makeshift command center inside the Israeli embassy, Uzi Navot laid down the handset of his secure radio and snatched up the receiver of his telephone. He quickly dialed a number for Thames House, the riverfront headquarters of MI5, and ten seconds later heard the voice of Graham Seymour.

“Where is he now?” Seymour asked.

“Heading across Hampstead Heath toward Highgate. They just told him that if he has a radio or a weapon on him at the next stop, Elizabeth Halton will be executed immediately. In a few seconds he’s going to be off the air.”

“What can we do for you?”

“Trace a telephone.”

“Give me everything you have on it.”

Navot gave Seymour the model and telephone number.

“I don’t suppose they were foolish enough to leave any information in the calling history.”

“The phone was clean, Graham.”

“We’ll run it and see if we come up with anything. But I wouldn’t hold out much hope. Unfortunately, there is no shortage of jihadists in our local telecommunications industry. They’re damned clever when it comes to covering their tracks with phones.”

“Just give us anything you come up with.”

Navot slammed down the phone and picked up the radio handset again. He grunted a few words in terse Hebrew, then looked at Shamron. He was pacing the room slowly, leaning heavily on his cane.

“You’re wasting your time chasing that phone, Uzi. You should be chasing the watchers instead.”

“I know, boss. But where are the watchers?”

Shamron stopped in front of a computer monitor and peered at a grainy night-vision image of four young men playing football outside the padlocked Hampstead Heath running track.

“At least one of them is right there in front of you, Uzi.”

“We’ve had them under watch since before Gabriel arrived. No phone calls. No text messaging. Only football.”

“Then you should assume that’s what the Sphinx told him to do,” Shamron said. “That’s the way I would have done it-an old-school, physical signal. If Gabriel is clean, keep playing football. If Gabriel is being followed, have an argument of some sort. If Gabriel has a radio, take a cigarette break.” Shamron poked at the screen. “Like that boy is doing right there.”

“You think one of them is a spotter?”

“I’d bet my life on it, Uzi.”

“That means that there’s someone else in the heath who can see him-someone with a cell phone or a two-way pager.”

“Exactly,” said Shamron. “But you’re never going to find him. He’s already gone by now. Your only option is to follow the spotter.”

Navot looked at the screen. “I don’t have the resources to follow four men.”

“You don’t have to follow four. You only have to follow one. Just make sure you pick the right one.”

“Which one is that?”

“Eli has good instincts about these things,” Shamron said. “Let Eli decide. And whatever you do, make sure you get another beacon on Gabriel before he leaves Highgate. If we lose him now, we might never find him again.”

Navot reached for his radio. Shamron started pacing again.

Gabriel jettisoned the Browning and the radio in a stand of trees at the center of the heath, then crossed the levee between the Highgate Ponds and made his way to Millfield Lane. Taped to the nearest lamppost was a snapshot of a dark blue BMW station wagon. The car itself was fifty yards farther along the lane, outside a large freestanding brick house with a string of smiling reindeer on the lawn. Gabriel opened the rear hatch and peered inside. The keys lay in plain sight, in the center of the cargo area. He removed them, placed the bags inside, then subjected the vehicle to a thorough inspection before climbing behind the wheel and tentatively turning the key.

The engine started right away. Gabriel opened the glove box and saw a single sheet of paper, which he examined by the ambient light of the dashboard. Listed on the page was a detailed set of driving instructions-a journey that would take him from Highgate to a headland for the distant reaches of Essex appropriately named Foulness Point. On the passenger seat was a well-thumbed Bartholomew Road Atlas. It was dated 1995 and opened to map number 25. The drop site was was marked with an X. The surrounding waters were labeled in red: DANGER ZONE.