By the time we arrived back at the villa, I had come to a decision. Danger or no danger, I was going to confront that gardener. I wanted to hear from his own lips exactly what he had seen that afternoon. Surely I’d know if he had told a lie. I helped Franz unload the motorcar, carrying the packages in to oohs and aahs of delight from my mother, who had already done an amazing job decorating the terrace with fairy lights and white-clothed tables. Ice buckets stood ready, as did small plates and forks and serving dishes.

“The food is all ordered. We’ve got masses of champagne on ice and more arriving any minute. Forty people have already said they are coming,” she said happily, “and they will all tell their friends, so we’ll wind up with a good crowd.”

I had a sudden thought. “Can I invite Binky?” I said. “I know it will mean Fig too, but he’s having such a dreary time at that awful villa, and he is such a good soul at heart.”

“The more the merrier, darling. You know how fond I am of him,” Mummy said.

I telephoned and the dragon agreed to pass on the message to the duke. Well, I’d done my part. Now for something a little more difficult. I went upstairs and deliberately put on the blue and white sailor outfit. Then I told the policeman standing outside our front gate that I wished to speak to Sir Toby’s gardener. He conferred with the policeman guarding Sir Toby’s gate.

“Not possible, mademoiselle,” he said. Why couldn’t these Frenchmen get the concept of “my lady” into their heads?

“And why not? This man’s evidence has convinced your inspector that I am guilty. I want to find out for myself what he really saw. One of you can come with me, if you like.”

The two men exchanged glances, then gave that Gallic shrug. “Why not?” one said. “I will accompany her.”

The address was obtained and we walked up the road until we came to a row of cottages. A woman answered our knock, wiping her hands on her apron.

“But my husband has not come home yet,” she said. “I thought maybe you police have required him to give his testimony again at headquarters.”

“Possible,” my policeman said. “But I know nothing of this. I will ask.”

So we walked back to Sir Toby’s property. An impressively high wall of rough stone bordered the road, cutting off any view of the villa, but I noticed that there was a small door in the wall. Presumably the gardener entered the property this way, rather than through the impressive main gate. I tried the door and it swung open.