Danvers-Smith was not proving to be the sort of fellow who habitually broke the speed limit. "His days as a test pilot are obviously long behind him," Donald said, as we trailed the Allegro at a safe distance into the next village. About half a mile later he pulled into a petrol station.

"Stay with him," said Donald. Jenny followed the Allegro into the forecourt and came to a halt at the pump directly behind Danvers-Smith.

"Keep your head down, Mr. Cooper," said the Don, opening his door. "We don't want him seeing you."

"What are you going to do?" I asked, peering between the front seats.

"Risk an old con's trick," Donald replied.

He stepped out of the front seat, walked around to the back of the car, and unscrewed the gas cap just as the wing commander slipped the nozzle of a gas pump into the tank of his Allegro. Donald began slowly topping up our already full tank, then suddenly turned to face the old man.

"Wing Commander Danvers-Smith?" he asked in a plummy voice.

The wing commander looked up immediately, and a puzzled expression came over his weather-beaten face.

"Baker, sir," said Donald. "Flight Lieutenant Baker. You lectured me at RAF Locking. Vulcans, if I remember."

"Bloody good memory, Baker. Good show," said Danvers-Smith. "Delighted to see you, old chap," he said, taking the nozzle out of his car and replacing it in the pump. "What are you up to nowadays?"

Jenny stifled a laugh.

"Work for BA, sir. Grounded after I failed my eye test. Bloody desk job, I'm afraid, but it was the only offer I got."

"Bad luck, old chap," said the wing commander, as they headed off toward the pay booth, and out of earshot.

When they came back a few minutes later, they were chattering away like old chums, and the wing commander actually had his arm round Donald's shoulder.

When they reached his car they shook hands, and I heard Donald say "Goodbye, sir," before Danvers-Smith climbed into his Allegro. The old airman pulled out of the forecourt and headed back toward his home. Donald got in next to Jenny and pulled the passenger door closed.

"I'm afraid he won't lead us to Alexander," the Don said with a sigh. "Danvers-Smith is the genuine article-misses his wife, doesn't see his children enough, and feels a bit lonely. Even asked if I'd like to drop in for a bite of lunch."

"Why didn't you accept?" I asked.

Donald paused. "I would have, but when I mentioned that I was from Leeds, he told me he'd only been there once in his life, to watch a test match. No, that man has never heard of Rosemary Cooper or Jeremy Alexander-I'd bet my pension on it. So, now it's the turn of the professor. Let's head back toward Cambridge, Jenny. And drive slowly. I don't want to catch up with the wing commander, or we'll all end up having to join him for lunch."

Jenny swung the car across the road and into the far lane, then headed back toward the city. After a couple of miles Donald told her to pull into the side of the road just past a sign announcing the Shelford Rugby Club.

"The professor and his wife live behind that hedge," Donald said, pointing across the road. "Settle back, Mr. Cooper. This might take some time."

At 12:30 Jenny went off to get some fish and chips from the village. I devoured them hungrily. By 3:00 I was bored stiff again, and was beginning to wonder just how long Donald would hang around before we were allowed to return to the hotel. I remembered Happy Days would be on at 6:30.

"We'll sit here all night, if necessary," Donald said, as if he were reading my thoughts. "Forty-nine hours is my record without sleep. What's yours, Jenny?" he asked, never taking his eyes off the house.

"Thirty-one, sir," she replied.

"Then this may be your chance to break that record," he said. A moment later, a woman in a white BMW nosed out of the driveway leading to the house and stopped at the edge of the sidewalk. She paused, looked both ways, then turned across the road and swung right, in the direction of Cambridge. As she passed us, I caught a glimpse of a blond with a pretty face.

"I've seen her before," I blurted out.

"Follow her, Jenny," Donald said sharply. "But keep your distance." He turned around to face me.

"Where have you seen her?" he asked, passing over the binoculars.

"I can't remember," I said, trying to focus on the back of a mop of fair, curly hair.

"Think, man. Think. It's our best chance yet," said Donald, trying not to sound as if he was cross-examining an old jailbird.

I knew I had come across that face somewhere, though I felt certain we had never met. I had to rack my brains, because it was at least five years since I had seen any woman I recognized, let alone one that striking. But my mind remained blank.

"Keep on thinking," said the Don, "while I try to find out something a little more simple. And Jenny-don't get too close to her. Never forget she's got a rearview mirror. Mr. Cooper may not remember her, but she may remember him."

Donald picked up the car phone and jabbed in ten numbers. "Let's pray he doesn't realize I've retired," he mumbled.

"DVLA Swansea. How can I help you?"

"Sergeant Crann, please," said Donald.

"I'll put you through."

"Dave Crann."

"Donald Hackett."

"Good afternoon, Chief Superintendent. How can I help you?"

"White BMW-K273 SCE," said Donald, staring at the car in front of him.

"Hold on please, sir, I won't be a moment."

Donald kept his eye fixed on the BMW while he waited. It was about thirty yards ahead of us, and heading toward a green light. Jenny accelerated to make sure she wouldn't get trapped if the lights changed, and as she shot through an amber light, Sergeant Crann came back on the line.

"We've identified the car, sir," he said. "Registered owner Mrs. Susan Balcescu, the Kendalls, High Street, Great Shelford, Cambridge. One endorsement for speeding in a built-up area, 1991, a thirty-pound fine. Otherwise nothing known."

"Thank you, Sergeant. That's most helpful."

"My pleasure, sir."

"Why should Rosemary want to contact the Balcescus?" Donald said as he clipped the phone back into place. "And is she contacting just one of them, or both?" Neither of us attempted to answer.

"I think it's time to let her go," he said a moment later. "I need to check out several more leads before we risk coming face to face with either of them. Let's head back to the hotel and consider our next move."

"I know it's only a coincidence," I ventured, "but when I knew him, Jeremy had a white BMW."

"F173 BZK," said Jenny. "I remember it from the file." Donald swung around. "Some people can't give up smoking, you know, others drinking. But with some, it's a particular make of car," he said. "Although a lot of people must drive white BMWs," he muttered almost to himself.

Once we were back in Donald's room, he began checking through the file he had put together on Professor Balcescu. The Times report of his escape from Romania, he told us, was the most detailed.

Professor Balcescu first came to prominence while still a student at the University of Bucharest, where he called for the overthrow of the elected government. The authorities seemed relieved when he was offered a place at Oxford, and must have hoped that they had seen the last of him. But he returned to Bucharest University three years later, taking up the position of tutor in politics. The following year he led a student revolt in support of Nicolae Ceauescu, and after he became president, Balcescu was rewarded with a cabinet post, as Minister of Education. But he soon became disillusioned with the Ceauescu regime, and within eighteen months he had resigned and returned to the university as a humble tutor. Three years later he was offered the Chair of Politics and Economics.

Professor Balcescu's growing disillusionment with the government finally turned to anger, and in 1986 he began writing a series of pamphlets denouncing Ceauescu and his puppet regime. A few weeks after a particularly vitriolic attack on the establishment, he was dismissed from his post at the university, and later placed under house arrest. A group of Oxford historians wrote a letter of protest to The Times but nothing more was heard of the great scholar for several years. Then, late in 1989, he was smuggled out of Romania by a group of students, finally reaching Britain via Bulgaria and Greece.

Cambridge won the battle of the universities to tempt him with a teaching job, and he became a fellow of Gonville and Caius in September 1990. In November 1991, after the retirement of Sir Halford McKay, Balcescu took over the Chair of Eastern European Studies.

Donald looked up. "There's a picture of him taken when he was in Greece, but it's too blurred to be of much use."

I studied the black-and-white photograph of a bearded middle-aged man surrounded by students. He wasn't anything like Jeremy. I frowned. "Another blind alley," I said.

"It's beginning to look like it," said Donald. "Especially after what I found out yesterday. According to his secretary, Balcescu delivers his weekly lecture every Friday morning, from ten o'clock to eleven."

"But that wouldn't stop him from taking a call from Rosemary at midday," interrupted Jenny.

"If you'll allow me to finish," said Hackett sharply. Jenny bowed her head, and he continued. "At twelve o'clock he chairs a full departmental meeting in his office, attended by all members of staff. I'm sure you'll agree, Jenny, that it would be quite difficult for him to take a personal call at that time every Friday, given the circumstances."

Donald turned to me. "I'm sorry to say we're back where we started, unless you can remember where you've seen Mrs. Balcescu."

I shook my head. "Perhaps I was mistaken," I admitted.

Donald and Jenny spent the next few hours going over the files, even checking every one of the ten phone numbers a second time.

"Do you remember Rosemary's second call, sir?" said Jenny, in desperation. "The director's not in at the moment' Might that be the clue we're looking for?"

"Possibly," said Donald. "If we could find out who the director is, we might be a step nearer to Jeremy Alexander."

I remember Jenny's last words before I left for my room. "I wonder how many directors there are in Britain, Chief."

Over breakfast in Donald's room the following morning, he reviewed all the intelligence that had been gathered to date, but none of us felt we were any nearer to a solution.

"What about Mrs. Balcescu?" I said. "She may be the person taking the call every Friday at midday, because that's the one time she knows exactly where her husband is."

"I agree. But is she simply Rosemary's messenger, or is she a friend of Jeremy's?" asked Donald.

"Perhaps we'll have to tap her phone to find out," said Jenny.

Donald ignored her comment, and checked his watch. "It's time to go to Balcescu's lecture."

"Why are we bothering?" I asked. "Surely we ought to be concentrating on Mrs. Balcescu."

"You're probably right," said Donald. "But we can't afford to leave any stone unturned, and since his next lecture won't be for another week, we may as well get it over with. In any case, we'll be out by eleven, and if we find Mrs. Balcescu's phone is engaged between twelve and twelve thirty ..."

After Donald had asked Jenny to bring the car around to the front of the hotel, I slipped back into my room to pick up something that had been hidden in the bottom of my suitcase for several weeks. A few minutes later I joined them, and Jenny drove us out of the hotel parking lot, turning right into the main road. Donald glanced at me suspiciously in the rearview mirror as I sat silently in the back. Did I look guilty? I wondered.

Jenny spotted a parking meter a couple of hundred yards away from the Department of European Studies, and pulled in. We got out of the car and followed the flow of students along the sidewalk and up the steps. No one gave us a second look. Once we had entered the building, Donald whipped off his tie and slipped it in his jacket pocket. He looked more like a Marxist revolutionary than most of the people heading toward the lecture.

The lecture hall was clearly signposted, and we entered it by a door on the ground floor, which turned out to be the only way in or out. Donald immediately walked up the raked auditorium to the back row of seats. Jenny and I followed, and Donald instructed me to sit behind a student who looked as if he spent his Saturday afternoons playing lock forward for his college rugby team.

While we waited for Balcescu to enter the room, I began to look around. The lecture hall was a large semicircle, not unlike a miniature Greek amphitheater, and I estimated that it could hold around three hundred students. By the time the clock on the front wall read 9:55 there was hardly a seat to be found. No further proof was needed of the professor's reputation.

I felt a light sweat forming on my forehead as I waited for Balcescu to make his entrance. As the clock struck ten the door of the lecture hall opened. I was so disappointed at the sight that greeted me that I groaned aloud. He couldn't have been less like Jeremy. I leaned across to Donald. "Wrong-colored hair, wrong-colored eyes, about thirty pounds too light." The Don showed no reaction.

"So the connection has to be with Mrs. Balcescu," whispered Jenny.

"Agreed," said Donald under his breath. "But we're stuck here for the next hour, because we certainly can't risk drawing attention to ourselves by walking out. We'll just have to make a dash for it as soon as the lecture is over. We'll still have time to see if she's at home to take the twelve o'clock call." He paused. "I should have checked the layout of the building earlier." Jenny reddened slightly, because she knew I meant you.

And then I suddenly remembered where I had seen Mrs. Balcescu. I was about to tell Donald, but the room fell silent as the professor began delivering his opening words.

"This is the sixth of eight lectures," he began, "on recent social and economic trends in Eastern Europe." In a thick Central European accent, he launched into a discourse that sounded as if he had given it many times before. The undergraduates began scribbling away on their pads, but I became increasingly irritated by the continual drone of the professor's nasal vowels, as I was impatient to tell Hackett about Mrs. Balcescu and to get back to Great Shelford as quickly as possible. I found myself glancing up at the clock on. the wall every few minutes. Not unlike my own schooldays, I thought. I touched my jacket pocket. It was still there, even though on this occasion it would serve no useful purpose.

Halfway, through the lecture, the lights were dimmed so the professor could illustrate some of his points with slides. I glanced at the first few graphs as they appeared on the screen, showing different income groups across Eastern Europe related to their balance of payments and export figures, but I ended up none the wiser, and not just because I had missed the first five lectures.

The assistant in charge of the projector managed to get one of the slides upside down, showing Germany at the bottom of the export table and Romania at the top, which caused a light ripple of laughter throughout the hall. The professor scowled, and began to deliver his lecture at a faster and faster pace, which only caused the assistant more difficulty in finding the right slides to coincide with the professor's statements.

Once again I became bored, and I was relieved when, at five to eleven, Balcescu called for the final graph. The previous one was replaced by a blank screen. Everyone began looking round at the assistant, who was searching desperately for the slide. The professor became irritable as the minute hand of the clock approached eleven. Still the assistant failed to locate the missing slide. He flicked the shutter back once again, but nothing appeared on the screen, leaving the professor brightly illuminated by a beam of light. Balcescu stepped forward and began drumming his fingers impatiently on the wooden lectern. Then he turned sideways, and I caught his profile for the first time. There was a small scar above his right eye, which must have faded over the years, but in the bright light of the beam it was clear to see.

"It's him!" I whispered to Donald as the clock struck eleven. The lights came up, and the professor quickly left the lecture hall without another word.

I leaped over the back of my bench seat, and began charging down the gangway, but my progress was impeded by students who were already sauntering out into the aisle. I pushed my way past them until I had reached ground level, and bolted through the door by which the professor had left so abruptly. I spotted him at the end of the corridor. He was opening another door, and disappeared out of sight. I ran after him, dodging in and out of the chattering students.

When I reached the door that had just been closed behind him I looked up at the sign: PROFESSOR BALCESCU.

DIRECTOR OF EUROPEAN STUDIES.

I threw the door open, to discover a woman sitting behind a desk checking some papers. Another door was closing behind her.

"I need to see Professor Balcescu immediately," I shouted, knowing that if I didn't get to him before Hackett caught up with me, I might lose my resolve.

The woman stopped what she was doing and looked up at me. "The director is expecting an overseas call at any moment, and cannot be disturbed," she replied. "I'm sorry, but-"

I ran straight past her, pulled open the door, and rushed into the room, where I came face to face with Jeremy Alexander for the first time since I had left him lying on the floor of my drawing room. He was talking animatedly on the phone, but he looked up and recognized me immediately. When I pulled the gun from my pocket, he dropped the receiver. As I took aim; the blood suddenly drained from his face.

"Are you there, Jeremy?" asked an agitated voice on the other end of the line. Despite the passing of time, I had no difficulty in recognizing Rosemary's strident tones.

Jeremy was shouting, "No, Richard, no! I can explain! Believe me, I can explain!" as Donald came running in. He came to an abrupt halt by the professor's desk, but showed no interest in Jeremy.

"Don't do it, Richard," he pleaded. "You'll only spend the rest of your life regretting it." I remember thinking it was the second time he had ever called me Richard.

"Wrong, for a change, Donald," I told him. "I won't regret killing Jeremy Alexander. You see, he's already been pronounced dead once. I know, because I was sentenced to life imprisonment for his murder. I'm sure you're aware of the meaning of 'autrefois acquit,' and will therefore know that I can't be charged a second time with a crime I've already been convicted of and sentenced for. Even though this time they will have a body."

I moved the gun a few inches to the right, and aimed at Jeremy's. heart. I squeezed the trigger just as Jenny came charging into the room. She dived at my legs.

Jeremy and I both hit the ground with a thud.

Well, as I pointed out to you at the beginning of this chronicle, I ought to explain why I'm in jail-or, to be more accurate, why I'm back in jail.