Cloncurry. This was their very last name, and the very best hope. Forrester sorted through the papers and photos on his knee, as the rain spattered the windscreen. He and Boijer were in a hire car in northern France, heading south from Lille. Boijer was driving, Forrester was reading: fast. And hoping they were finally on the right track. It certainly looked good.

They’d spent the last few days talking to headmasters and rectors and student advisors, phoning reluctant doctors in university clinics. Quite a few likely candidates had emerged. A drop-out from Christ Church, Oxford. A couple of expellees from Eton and Marlborough. A schizophrenic student, missing from St Andrews. Forrester had been shocked at the number of students diagnosed as schizophrenic. Hundreds across the country.

But the candidates had all been ruled out, one way or another. The posh Oxford drop-out was in a mental hospital. The St Andrews student was known to be in Thailand. The Eton expellee had died. In the end they had drilled it down to one name: Jamie Cloncurry.

He had all the right credentials. His family was extremely wealthy, and of aristocratic descent. He’d been very expensively schooled at Westminster where his behaviour, according to his housemaster, was eccentric verging on violent. He had beaten another pupil and come perilously close to expulsion. But his academic brilliance had afforded him a second chance.

Cloncurry had then gone to Imperial College in London to study mathematics. One of the finest scientific universities in the world. But this grand opportunity hadn’t solved his problems; indeed his wildness had only intensified. He’d dabbled in hard drugs and been caught with call-girls in his Hall of Residence. One of them had reported him to the police for brutality, but the Crown Prosecution Service had dropped the charge on the grounds of an unlikely conviction: she was a prostitute, he a gifted student at a top university.

Crucially, it seemed Cloncurry had gathered around him a number of extremely close friends-Italians, French and American. One of his fellow students said Cloncurry’s social circle was ‘a weird clique. Those guys worshipped him’. And, as Boijer and Forrester had established, in the last two or three weeks that clique had disappeared. They hadn’t been seen at lectures. A concerned sibling had reported her brother as missing. The college had posters of him in the union bar. An Italian kid: Luca Marsinelli.

The young men had left no trace. Their student digs were empty of evidence. No one knew or even especially cared where they had gone. The clique members were disliked. Acquaintances and neighbours were bafflingly vague. ‘Students come and go all the time.’ ‘I thought he’d gone back to Milan’. ‘He just said he was taking a holiday.’

At Scotland Yard they had therefore been obliged to make some tough decisions. Forrester’s team couldn’t follow every lead with equal zeal. Time was running out. The Toyota Landcruiser had been found, abandoned, on the outskirts of Liverpool, the gang having evidently guessed that the car was a liability. The gang had gone to ground, but Forrester knew they would surely strike again, and soon. But where? There wasn’t time for speculation. So Forrester had ordered his team to zero in on Cloncurry, the alleged leader.

The Cloncurry family lived, it turned out, in Picardy in Northern France. They had an ancestral home in Sussex, a large flat in London, and even a villa in Barbados. But for some reason they lived in the middle of Picardy. Near Albert. Which was why Forrester and Boijer had caught the first Eurostar this morning from London St Pancras to Lille.

Forrester surveyed the huge and rolling fields, the pinched little woods; the grey and steely sky of northern France. Every so often, one of the hills would be adorned by another British wartime cemetery: a lyrical but melancholy parade of chaste marble headstones. Thousands and thousands of graves. It was a depressing spectacle, not helped by the rain. The trees were in Maytime blossom, but even the blossom was wilted and helpless in the relentless drizzle.

‘Not the most attractive part of France, is it, sir?’

‘Hideous,’ Forrester answered. ‘All these cemeteries.’

‘Lots of wars here, right?

‘Yes. And dying industries. That doesn’t help.’ He paused, then said, ‘We used to come here on holiday.’

Boijer chuckled. ‘Nice choice.’

‘No not here. What I mean is we used to go camping in the south of France, when I was a kid. But we couldn’t afford to fly, so we had to drive all the way down through France. From Le Havre. And we used to come through here, through Picardy. Past Albert and the Somme and the rest of it. And every time I would cry. Because it was so bloody ugly. The villages are so ugly because they were all rebuilt after the Great War. In concrete. Millions of men died in these wet fields, Boijer. Millions. In Flanders Fields.’

‘I guess so.’

‘I think the Finns were still living in igloos at the time.’

‘Yes, sir. Eating moss.’

The two men laughed, quite laddishly. Forrester needed some light relief. The Eurostar journey had been equally sombre: they’d used the hours to go over the pathology reports one more time. To see if they’d missed anything. But nothing had jumped out at them. It was just the same chilling scientific analysis of the wounds. Extensive haemorrhage. Stab wound in the fifth intercostal. Death by traumatic asphyxia.

‘Think this is it,’ said Boijer.

Forrester checked the sign: Ribemont-sur-Ancre. 6km. ‘You’re right. This turn-off.’

The car swerved onto the slip road, scything through gathered pools of rainwater. Forrester wondered why it rained so much in north-east France. He remembered stories of Great War soldiers drowning in mud, literally drowning in their hundreds and thousands, in the churned wet rainy mud. What a way to die. ‘And take a right here.’

He checked the address of the Cloncurrys. He’d rung the family and got their agreement to an interview just a day ago. The mother’s voice was cold and slightly quavery on the phone. But she had given him instructions. Go past the rue Voltaire. A kilometre further on. Then take the left, towards Albert. ‘Take this left…’

Boijer swung the wheel and the hire car crunched through a rutted puddle; the road was virtually a farm track.

Then they saw the house. It was large and impressive, shuttered and dormered, with a severely sloping roof in the French style. But it was also sombre, dark and oppressive. An odd place to come and live.

Jamie Cloncurry’s mother was waiting for them at the end of the wide, looping driveway. Her accent was icily posh. Very English. Her husband was just inside the door, in an expensive tweed jacket and corduroys. His socks were bright red.

In the sitting room a maid served coffee. Mrs Cloncurry sat opposite them, with her knees pressed tightly together. ‘So, Inspector Forrester. You wish to talk about my son Jamie…’

The interview was painful. Stilted and laborious. The parents claimed they had lost control of Jamie in his mid teens. By the time he reached university they had lost all contact, too. The mother’s mouth twitched, very slightly, as she discussed Jamie’s ‘problems’.

She blamed drugs. And his friends. She confessed she blamed herself, as well, because they had sent him to boarding school-to be a boarder at Westminster. This had increased the young man’s isolation within the family. ‘And so he with-drew from us. And that was that.’

Forrester was frustrated. He could tell where the interview was going. The parents knew nothing: they had practically disclaimed their son.

As Boijer took over the questioning, the DCI scanned the large and silent sitting room. There were many family photos-of the daughter, Jamie’s sister. Photos of her on holiday, on a pony, or at her graduation. Yet no photos of the son. Not one. And there were family portraits too. A military figure: a Cloncurry from the nineteenth century. A viscount in the Indian Army. And an admiral. Generations of distinguished forebears were staring from the walls. And now possibly-probably-there was a murderer in the family. A psychotic killer. Forrester could feel the shame of the Cloncurrys. He could feel the pain of the mother. The father was practically silent during the interview.