An officer came in and removed Giovanni, who darted a look at Il Questore’s back and as he passed Alleyn rapidly mimed a spit into his face. The officer barked at him and pushed him out. Violetta, thought Alleyn, would not have stopped short at pantomime.

‘These students!’ cried Valdarno, leaving the telephone. ‘What do they suppose they achieve? Now, they burn up Vespa motorcycles. Why? Possibly they are other students’ Vespas. Again, why? You were speaking of the signed statement. I would be greatly obliged if you would combine with Bergarmi.’ The buzzer sounded. ‘Basta!’ shouted Il Questore and answered it.

Alleyn joined Bergarmi, who received him with a strange blend of huffishness and relief. He had written out a résumé in Italian, based on his own notes of the now desperately familiar experiences of the travellers in the depths of S. Tommaso. Alleyn found this accurate and put it into English. ‘Would you like a check of the translation by a third person, Signor Vice-Questore?’ he asked. Bergarmi made deprecatory noises. ‘After all,’ he said, ‘it is no longer of the first importance, all this. Giovanni Vecchi’s evidence and the fact that this—’ he slapped the statement ‘—does nothing to contradict it and, above all, Sweet’s attempt to escape, are sufficient, for our purpose. The case is virtually closed.’

Alleyn pushed his translation across the table. ‘There is just one thing I’d like to suggest.’

‘Yes? And that is?’

‘The Van der Veghels took photographs in the Mithraeum and the insula. Flashlights. Two by the Baroness and one by the Baron. Kenneth Dorne also took one. After that, when we were returning, the Baroness photographed the sarcophagus. I thought you might like to produce these photographs.’

‘Ah. Thank you. The sarcophagus, yes. Yes. That might be interesting.’

‘If it shows the piece of shawl?’

‘Quite so. It would limit the time. To some extent that is true. It would show that the woman Violetta was murdered before you all left the Mithraeum. By Mailer, of course. There can be no doubt, by Mailer. It would not help us—not that we need this evidence—to fix a precise time for Sweet’s attack upon Mailer. We have, my dear Signor Super,’ said Bergarmi with evident pleasure in discovering this new mode of address, ‘motive. From your own investigation of Sweet.’ Alleyn made a wry face. ‘Intent. As evidenced in suspicious behaviour noted by Vecchi. Opportunity. Apart from Signor Dorne and his Aunt Baroness (this latter being a ludicrous notion), he is the only one with opportunity.’

‘With the greatest respect—the only one?’

‘Signore?’

‘Well,’ Alleyn said apologetically, ‘it’s just that I wonder if Giovanni was speaking all of the truth all of the time.’

After a considerable pause Bergarmi said, ‘I find no occasion to doubt it.’ And after an even longer pause: ‘He had no motive, no cause to attack Mailer.’