"You may be right about keeping Sosia Camillina out of sight," he said. "Is your hideout respectable?"

"Supervised by my own mother, sir!" True: she scoured my rooms regularly for evidence of loose women. Sometimes she found it, sometimes I hustled them out in time.

This senator was no idiot. He decided someone had to come back with me to make sure the wench was safe. I advised him against that. I had seen some greasy meatballs in the cook shop opposite, watching visitors to his home. There was nothing to say they were connected with Sosia, they could have been casual burglars who had picked an unlucky day to size up a future break-in. Since he was walking me round his property anyway, we went to look.

On the front door they had a sound wooden lock with a six inch, three-toothed iron rotary key, plus four brass bolts, an inspection grille with a natty little slider, and a great holm oak beam inside to sling across on two well-bedded cradles at night. The door porter lived in a cubbyhole at the side.

"Adequate?" remarked the senator.

I gave him a long look, including the dozy sprite they used as a doorman the slack-mouthed strip of wind who had let Sosia's abductors walk in.

"Oh yes, sir! A wonderful system, so let me offer some advice: use it!" I could see he took the point.

I made him peer through the grille to inspect the two loafers in the cook shop

"Those peepers saw me come. I'll hop out over your back wall; give me a chance to survey the rear of the house. Send a slave to the local lockup and get them arrested for causing a breach of the peace."

"But they are not"