Nonetheless, they found their way up to the first-class lounge, and ordered hot sandwiches for lunch. The stewardess would bring them complimentary coffee throughout the journey.

The summer sea was calm, and the ferry, a giant hovercraft, charged toward the United Kingdom in a blizzard of howling spray, ripping past a regular shaft-driven ferryboat as if it had stopped.

Holyhead, their destination, sits on Holy Isle, the northwest point of Wales, jutting out into the Irish Sea. This in turn is joined to the ancient twenty-mile-long Isle of Anglesey where the A-5, the main road into England, begins. Or ends, depending on your direction.

Ravi and Shakira had to wait for the cars and trucks to leave the ship before foot passengers were permitted to walk off. They joined a busy line of mostly young people going through the passport control area, and twenty minutes later, with only the most cursory glance at one of Shakira’s four passports, the British one for Margaret Adams, they waved her through.

Ravi, the former British Army officer, said “good afternoon” crisply in that unmistakable tone the British use to intimidate the lower orders, and was waved through immediately. The official paid hardly any attention to this well-dressed Charles Larkman, in his expensive brown suede jacket and white T-shirt.

However, the closed-circuit camera behind him was more observant, and there was a photographic record that Miss Adams and Mr. Larkman had indeed entered the United Kingdom, off the two o’clock ferry from Dublin, on July 17.

From the immigration area, they walked to the car-rental desks, and Shakira hired an Audi A6 for a month, using her new American Express Gold Card, originally issued to a staff member at the Syrian embassy in London. She offered one of her three driver’s licenses, the one in the name of Margaret Adams, and Ravi booked himself in as an extra driver using Mr. Larkman’s clean British license.

Thankfully, they stowed their two bags in the trunk and set off on the long 300-mile journey to London, Ravi at the wheel.

The regular route for most drivers is to cross the Menai Strait onto the mainland and then travel all along the North Wales coast until it reaches the fast motorway system south of Liverpool. Ravi would do it differently, driving through the mountains of North Wales, southeast to Shrewsbury, and then south into Hereford, home of the British Army’s elite SAS, his old stomping ground. It was perhaps the irresistible urge of the outlaw to return, in the broadest possible sense, to the scene of the crime.

Shortly after 5 P.M., the two officers from New Scotland Yard agreed to consult with MI-6, Britain ’s overseas intelligence agency. It was clear to both of them that the man who killed Jerry O’Connell was no passing villain: this was a man who had almost certainly made illegal entry into Ireland, and if challenged in any way would kill ruthlessly and without compunction.

Both men had previous experience with such operators, mostly in the field of counterterrorism. The IRA had men like that, and the various jihadist organizations were full of them. Fanatics.

At the heart of the O’Connell killing was the fact that the murderer had been trained militarily. No one can kill like that, not without expert instruction. MI-6 listened attentively and promised to make immediate inquiries, find out if there was a rogue Special Forces operator on the loose.

One hour later, it was clear that MI-6 had raised a serious hue and cry. They’d talked to the CO at Stirling Lines, headquarters of the SAS; they’d touched base with military intelligence in all three branches of the service. They even heard about the suspect Iranian submarine, and it seemed everyone in the entire intelligence community understood there was something very strange about the death of the Irish farmer.

At 7 P.M. in England, 2 P.M. on the East Coast of the United States, the FBI was put in the picture. This was no longer an Irish-country-murder inquiry; this was now a preliminary examination of a possible terrorist on the loose in the British Isles. Jimmy Ramshawe, who was no longer in the office, was informed by a young duty officer that his buddy in the FBI had called and wanted to talk urgently.

Jimmy was in his apartment at the Watergate with Jane when the message came through. He called back and listened as the agent explained that the Special Branch had flown into Ireland from Scotland Yard and all hell seemed to be breaking loose over the death of the Irish farmer.

“Any idea why?” asked Jimmy innocently, hardly able to contain his excitement.

“Yeah. He was apparently killed by an unarmed combat blow which could only have been delivered by a Special Forces guy, you know, a Navy SEAL or an SAS man.”

“I KNEW IT!” yelled Jimmy.

“Knew what?”

“I knew there was something going on in connection with southern Ireland.”

“Not to mention southern Virginia. Christ, Jimmy, we’ve made more calls for you than we have for ourselves. Carla Martin, Maureen Whatsername, Aer Lingus, Shelbourne Hotel, passports, embassies. I gotta tell you, buddy, it looks like there might be some connection here-”

“NO SHIT!” yelled Jimmy, ungraciously. He thanked his buddy for the call, pressed the cutoff button, and dialed Admiral Morgan.

And once more he related the myriad of “disconnected facts” that suggested to him that someone was going to make an attempt on the life of the president’s most trusted adviser, scourge of the Middle Eastern terrorists.

But this time he was leading up to a payoff line. And with something of a flourish, he revealed the priceless information to the admiral: that the Irish farmer had been killed by a blow which could only have been delivered by a member, or at least a former member, of the U.S. or British Special Forces.

“You’re telling me, Jimmy, that someone hopped off that Iranian submarine, right out there in the Irish Sea, and killed the farmer on his way to killing me?”

“Well, not exactly. But I do know that an agent, wielding a Syrian dagger, befriended your mother-in-law very deliberately and then vanished from the face of the earth, in the full knowledge of your arrival time and hotel reservation in London on Tuesday, July 31.

“And that female agent, in my opinion, went to Ireland. Where the submarine was, and where another agent, a colleague and Special Forces guy, has just committed a murder on the way to his final destination, which might just be the Ritz Hotel.”

“Steady, kid. There’s too many gaps. Too few real links. Although I recognize the death of the Irish farmer is significant, and according to your story it does look as if the killer might have got off that submarine.”

“Arnie, will you cancel London?”

“Hell, no. I got a lot of security around me. I’ll be fine. You can’t let ’em rule you, kid, otherwise they’ve won. And we’re not gonna let that happen, right?”

Jimmy ended the phone call, and contemplated the sheer futility of trying to convince Admiral Morgan that he might be in danger. And he racked his brains to think of a link, or even a terror suspect who might have killed Jerry O’Connell.

He pulled up his most-wanted list of Middle Eastern hard men, guys suspected of heinous crimes against humanity, guys who’d killed and maimed in Israel, murdered in Jordan, committed atrocities in Iraq and Afghanistan and at various U.S. embassies in Africa.

Had one of them traveled to Ireland in the missing Kilo? And why Ireland? Arnie wasn’t going there. He tried to put himself in the shoes of the terrorist, and went through a process he had perfected years ago: