The massive castle keep, the central stronghold, was thirty-five yards long by twenty-six wide, with its imposing walls still standing over sixty feet above the surrounding grass apron. That, in turn, had originally been enclosed on all four sides by high outer curtain walls, against which had once been built accommodations, stores, ovens, guardrooms and a chapel. Nowadays, these outer walls remained intact only on the north, west and south sides, having collapsed along half its length on the east.

However, the structure I found most intriguing was the latrine tower set into the centre of the western outer wall, where the several primitive medieval toilet cubicles had once included special chutes to send the human waste out through the wall into the dry moat beyond.

Finally, I took the steep internal stone spiral staircase to the high observation point at the top of the south-east corner of the keep, and, sure enough, there was a good view down into Simon Paulson’s training yard.

Above me, the sky was darkening with threatening rain clouds, so I quickly descended and made my way back to the Discovery.

The policeman had gone but, even so, I decided not to clamber again onto the Swine Cross. Most of the horses were now safely back in their stables anyway, after their morning exertions on the gallops.

I climbed into the vehicle and drove off.

Only as it started to rain and the Land Rover’s automatic system turned on the windscreen wipers, did I notice that there was a small piece of yellow paper stuck under the driver’s side blade.

I pulled over at the marketplace to remove it.

The paper was about two inches by one and it had a telephone number scribbled on it in black ink.

I dialled the number. It was answered at the first ring as if someone had been waiting for my call.

‘Hello,’ said a young male voice.

‘I’m Sid Halley,’ I said. ‘Who is this?’

‘You don’t need to know that,’ came the reply.

‘Okay,’ I said. ‘But why did you want me to call you?’

‘I hear that you are looking for Anton Valance?’

‘Indeed I am.’

‘Why do you want him?’

‘You don’t need to know that,’ I said, echoing his earlier reply to me. ‘Not unless you are, indeed, Anton Valance.’

‘I am not.’

‘So how do I find him?’ I asked.

‘You don’t need to. He’ll find you. He knows you’re looking for him.’

‘How does he know that?’

‘Because I told him. I heard you shouting it earlier in the town.’

‘So if you’ve already told him that I’m looking for him, why did you then bother to leave your telephone number under my windscreen wiper?’

There was a slight pause from the other end as if the caller was now sorry he had.

‘I just felt I should tell you, that’s all.’

‘Why?’ I asked.