“I don’t know.” Jaeger’s face was suddenly drawn and hard. “What’s more, I don’t want to know.”

A STEEP flight of stone steps led down to the semi-darkness. At the bottom, March hesitated, the chocolates in his hand. A doorway to the left led out to the cobbled centre courtyard, where the rubbish was collected from large, rusty bins. To the right, a dimly lit passage led to the Registry.

He tucked the chocolates under his arm and turned right.

The Kripo Registry was housed in what had once been a warren of rooms next to the boilerhouse. The closeness of the boilers and the web of hot water pipes criss-crossing the ceiling kept the place permanently hot. There was a reassuring smell of warm dust and dry paper, and in the poor light, between the pillars, the wire racks of files and reports seemed to stretch to infinity.

The Registrar, a fat woman in a greasy tunic who had once been a wardress at the prison in Plotzensee, demanded his ID. He handed it to her, as he had done more than once a week for the past ten years. She looked at it, as she always did, as if she had never seen it before, then at his face, then back, then returned it, and gave an upward tilt of her chin, something between an acknowledgement and a sneer. She wagged her finger. “And no smoking,” she said, for the five-hundredth time.

From the shelf of reference books next to her desk he selected Wer Ist’s?, the German Who’s Who — a red-bound directory a thousand pages thick. He also took down the smaller, Party publication, Guide to the Personalities of the NSDAP, which included passport-sized photographs of each entrant. This was the book Halder had used to identify Buhler that morning. He lugged both volumes across to a table, and switched on the reading light. In the distance the boilers hummed. The Registry was deserted.

Of the two books, March preferred the Party’s Guide. This had been published more or less annually since the mid-1930s. Often, during the dark, quiet afternoons of the winter, he had come down to the warmth to browse through old editions. It intrigued him to trace how the faces had changed. The early volumes were dominated by the grizzled ex-Freikorps red-baiters, men with necks wider than their foreheads. They stared into the camera, scrubbed and ill at ease, like nineteenth-century farmhands in their Sunday best. But by the 1950s, the beer-hall brawlers had given way to the smooth technocrats of the Speer type — well-groomed university men with bland smiles and hard eyes.

There was one Luther. Christian name: Martin. Now here, comrades, is an historic name to play with. But this Luther looked nothing like his famous namesake. He was pudding-faced with black hair and thick horn-rimmed glasses. March took out his notebook.

Born: 16 December 1895, Berlin. Served in the German Army transport division, 1914-18. Profession: furniture remover. Joined the NSDAP and the SA on 1 March 1933. Sat on the Berlin City Council for the Dahlem district. Entered the Foreign Office, 1936. Head of Abteilung Deutschland — the “German Division” — of the Foreign Office until retirement in 1955. Promoted to Under State Secretary, July 1941.

The details were sparse, but clear enough for March to guess his type. Chippy and aggressive, a rough-and-tumble street politician. And an opportunist. Like thousands of others, Luther had rushed to join the Party a few weeks after Hitler had come to power.

He flicked through the pages to Stuckart, Wilhelm, Doctor of Law. The photograph was a professional studio portrait, the face cast in a film star’s brooding half-shadow. A vain man, and a curious mixture: curly grey hair, intense eyes, straight jawline — yet a flabby, almost voluptuous mouth. He took more notes.

Born 16 November 1902, Wiesbaden. Studied law and economics at Munich and Frankfurt-am-Main universities. Graduated Magna Cum Laude, June 1928. Joined the Party in Munich in 1922. Various SA and SS positions. Mayor of Stettin, 1933. State Secretary, Ministry of the Interior, 1935-53. Publication: A Commentary on the German Racial Laws (1936). Promoted honorary SS-Obergruppenfuhrer, 1944. Returned to private legal practice, 1953.

Here was a character quite different from Luther. An intellectual; an alter Kampfer, like Buhler; a high-flyer. To be Mayor of Stettin, a port city of nearly 300,000, at the age of thirty-one… Suddenly, March realised he had read all this before, very recently. But where? He could not remember. He closed his eyes. Come on.

Wer Ist’s? added nothing new, except that Stuckart was unmarried whereas Luther was on his third wife. He found a clean double-page in his notebook and drew three columns; headed them Buhler, Luther and Stuckart; and began making lists of dates. Compiling a chronology was a favourite tool of his, a method of finding a pattern in what seemed otherwise to be a fog of random facts.

They had all been born in roughly the same period. Buhler was sixty-four; Luther, sixty-eight; Stuckart, sixty-one. They had all become civil servants in the 1930s -Buhler in 1939, Luther in 1936, Stuckart in 1935. They had all held roughly .similar ranks — Buhler and Stuckart had been state secretaries; Luther, an under state secretary. They had all retired in the 1950s- Buhler in 1951, Luther in 1955, Stuckart in 1953. They must all have known one another. They had all met at 10 am the previous Friday. Where was the pattern?

March tilted back in his chair and stared up at the tangle of pipes chasing one another like snakes across the ceiling.

And then he remembered.

He pitched himself forward, on to his feet.

Next to the entrance were loosely bound volumes of the Berliner Tageblatt, the Volkischer Beobachter and the SS paper, Das Schwarzes Korps. He wrenched back the pages of the Tageblatt, back to yesterday’s issue, back to the obituaries. There it was. He had seen it last night.

Party Comrade Wilhelm Stuckart, formerly State Secretary of the Ministry of the Interior, who died suddenly of heart failure on Sunday, 13 April, will be remembered as a dedicated servant of the National Socialist cause…

The ground seemed to shift beneath his feet. He was aware of the Registrar staring at him. “Are you ill, Herr Sturmbannfuhrer?”

“No. I’m fine. Do me a favour, will you?” He picked up a file requisition slip and wrote out Stuckart’s full name and date of birth. “Will you see if there’s a file on this person?”

She looked at the slip and held out a hand. “ID.”

He gave her his identity card. She licked her pencil and entered the twelve digits of March’s service number on to the requisition form. By this means a record was kept of which Kripo investigator had requested which file, and at what time. His interest would be there for the Gestapo to see, a full eight hours after he had been ordered off the Buhler case. Further evidence of his lack of National Socialist discipline. It could not be helped.

The Registrar had pulled out a long wooden drawer of index cards and was marching her square-tipped fingers along the tops of them. “Stroop,” she murmured. “Strunck. Struss. Stulpnagel…”

March said: “You’ve gone past it.”

She grunted and pulled out a slip of pink paper. “ ‘Stuckart, Wilhelm.’ ” She looked at him. “There is a file. It’s out.”

“Who has it?”

“See for yourself.”

March leaned forwards. Stuckart’s file was with Sturm-bannfuhrer Fiebes of Kripo Department VB3. The sexual crimes division.

THE whisky and the dry air had given him a thirst. In the corridor outside the Registry was a water-cooler. He poured himself a drink and considered what to do.

What would a sensible man have done? That was easy. A sensible man would have done what Max Jaeger did every day. He would have put on his hat and coat and gone home to his wife and children. But for March that was not an option. The empty apartment in Ansbacher Strasse, the quarrelling neighbours and yesterday’s newspaper, these held no attractions for him. He had narrowed his life to such a point, the only thing left was his work. If he betrayed that, what else was there?