“Sir, once you think of it, it seems horribly obvious. I’ll go back to the start. When the first silver pig turned up in Rome, what happened to Sosia Camillina was deeply relevant; I have always thought that. Possibly Atius Pertinax, in his position as the praetor’s aedile, had been able to tell the conspirators where the ingot was hidden. But I now believe that they knew that already—and certainly it was someone close to her who realized that Sosia knew the number to the bank box. So, the speediest way to get into it was to take her there herself—using ruffians to confuse the issue and prevent her recognizing anyone.”

Titus nodded. “Anything else?”

“Yes. Just before she died, Sosia wrote to her cousin that she had identified the house of a man who was connected with the people who abducted her. I believe that is where she had found this list. The point is, at that time, for her own safety following the kidnap attempt she was confined at home—that is, in the senator’s house—though I have no doubt that whenever she wanted, she would still have been given access to her own father’s house next door.” Titus shook his head in reluctant acceptance of what I said. “Caesar, from the moment I undertook this case for you, someone very close has been watching my progress and thwarting every turn. When Helena Justina and I came back from Britain, after months away, someone knew enough to ambush us that very day. I had in fact sent a message from the Ostia Gate—to her family.”

“And so you lost the letter from friend Hilaris?” Titus smiled affectionately as he spoke; honest Gaius, with his pedantic dedication to hard work, had that effect. I smiled too, though simply because I liked the man.

“Quite. I always assumed the two names Flavius Hilaris was sending to Vespasian were Domitian and Pertinax. He would not tell me though. I misunderstood; it’s most unlikely the mining contractor Triferus would realize your brother was involved…Pertinax, the shipper, must be one of them, but Pertinax had been married to Gaius’ own niece. And suppose the other was an even closer relation of his wife’s? It must have been painful; no wonder if Flavius Hilaris preferred to stand aloof and let Vespasian decide what to do.”

Without comment on that point, Titus suggested carefully, “Did you ever consider Hilaris might be implicated here?”

“Not once I met him!” I told him my joke about this case being one where only the public officers were straight; he laughed.

“All honour to the knights,” he exclaimed, applauding the middle class. Then added, fully serious as far as I could tell, “You ought to consider aiming for higher rank yourself. My father is anxious to build up the lists with good men.”