‘We are to go to their dinner party the day he’s back and he’ll tell us everything!’ Adila grabbed her by the waist and whirled her round the hall in a manic waltz. ‘Today, I knew, there would be a miracle. It is found! Found!’

*

‘Found? If only it were that simple.’

In Portland Place Erik presided at the head of the table, with Adila to his right, Jelly to his left, Ebba at the far end with Alec beside her; the Palmstiernas’ daughter Margareta and her husband François were visiting from France and sat in the centre, one on each side; and, in between, more dinner party guests were arrayed in alternation of the sexes – men in black tie, women in sleek evening gowns, their jewels grabbing light from the chandelier above and the tall candles in the middle. Jelly, wearing crimson silk, and Adila, in lilac satin, both leaned towards the baron as he described his unlikely ambassadorial adventures in the music libraries of Berlin.

‘But what’s the concerto like?’ Jelly begged.

‘Unfortunately,’ said the baron, ‘it’s one of my great regrets that I have never learned to read music. So I’m afraid… ’

‘And they wouldn’t let you photograph it?’ Adila pressed.

Indeed they had not. It was pure chance he had found it at all. He had gone first to the Musikhochschüle library, where nothing was in evidence, but overhearing him talking to the librarian, a passing academic glanced round and suggested he try the Staatsbibliothek – the Prussian State Library – instead. There, some official in uniform barred his way, accusing him of being Jewish, prodding him in the chest with a gun. Erik, who was stocky and dark, had to produce three rounds of diplomatic papers before he was believed. Once inside, he found nothing of interest in files marked SCHUMANN, but acting on a hunch, well aware of the possibility of misfiling alongside misidentification, he decided to check those marked JOACHIM as well. This revealed a modest sheaf of faded manuscript paper signed with the name ‘Robert Schumann’.

Not that anybody at the library had been particularly aware of the treasure stashed away in their archive, but once they were – oh dear. That was just the start. For one thing, there were apparently several manuscripts of the same piece, in different formats; he had only found one of them. The archive’s head, hunting through some records, told him that another, the first movement with piano score, had been used for a play-through at Zwickau, Schumann’s birthplace, three years earlier, but was then laid to rest again. And last, but assuredly not least, a note accompanied the file, declaring that the concerto was ‘not for publication’. It was not to be performed until 100 years after Schumann’s death.

‘But it’s not lost at all, or even suppressed, if it’s been played?’ Ebba challenged her husband.