Sir Percival's spies attacked me on the road to Knowlesbury. One of them came up beside me, and bumped into me with his shoulder. I pushed him away, hard, and he immediately shouted for help. The other man ran up and the two of them held me between them. The first man accused me of attacking him, and they said they would take me to the police station in the town.

At the police station the first man accused me of a violent attack, and the second man said he was a witness. I was locked up until the next magistrate's court, which was three days away. I could be released on bail, I was told, but how could I, a total stranger in the town, find a responsible person willing to pay money for my temporary freedom? The whole plan was now clear -- to get me out of the way for three days, while Sir Percival did whatever was necessary to prevent his secret being discovered.

At first I was too angry to think clearly. Then I remembered Mr Dawson, the doctor. I had been to his house on my previous visit to Blackwater, so I knew his address. I wrote him a letter, explaining what had happened and begging for his help, and then asked for a messenger to deliver it. Two hours later the good doctor appeared, paid the required money and I was set free.

What could I do? I couldn't fight both of them and hope to get away, so I had to go with them.

There was no time to lose. The news of my being free would doubtless reach Sir Percival within hours. I hurried to the lawyer's office, where I asked if I could see the copy of the Welmingham marriage register. Mr Wansborough was a pleasant man and agreed to show me the copy. In fact, he was quite amused. No one had asked to see it since his father (now dead) had locked it away in the office more than twenty years before.

As I opened the register, my hands trembled. I turned the pages to the year and month. I found the names I remembered just before, and just after, the marriage of Sir Percival's parents. And between these entries, at the bottom of the page…?

Nothing! The marriage of Sir Felix Glyde and Cecilia Elster was not there! I looked again, to be sure. No, nothing. Not a doubt about it. Sir Percival must have seen the space in the Welmingham register and written in the marriage himself.

I had never once suspected this. He was not Sir Percival Glyde at all! His parents had not been married, so he had no right to the inheritance of Blackwater Park, no right to the rank of Baronet, no right even to the name of Glyde! This was his secret -- and it was now mine to use against him!

The copy of the register would be safe enough in the lawyer's office, but I decided to go back to Welmingham and make a copy of the false record from the church register. It was dark now and I ran all the way to the church clerk's house. I knocked on his door, but when he appeared, he looked suspicious and confused.

"Where are the keys?" he asked. "Have you taken them?"

"What keys do you mean?" I said. "I've just this minute arrived from Knowlesbury."

"The keys of the vestry," he said. "The keys are gone! Someone's broken in and taken the keys."

As we came in sight of the vestry, I saw a high window brilliantly lit from within. There was a strange smell on the night air, a sound of cracking wood, and the light grew brighter and brighter. I ran to the door and put my hand on it. The vestry was on fire!

"Get a light," I said, "and let's go to the vestry. Quick!"

We ran to the church. On the path we passed a man who looked at us with frightened eyes. He seemed to be a servant of some kind. We did not stop to question him, but ran on.

"Oh, my God!" said the servant, who had followed us, "it's Sir Percival!"

I heard the key working violently in the lock -- I heard a man's voice behind the door, raised in terror, screaming for help.

"God help him!" said the clerk. "He's damaged the lock."

By now the flames are shooting up out of the window, and the screams have stopped. We get the wood into position and run at the door with it. Again, and again! At last the door crashes down, but a wave of heat hits our faces and drives us back -- and in the room we see nothing but a sheet of living fire.

At that moment I forget the man's crimes and see only the horror of his situation. Several people are now running towards the church and I call to them to help me break down the door. We look desperately for something to use, and at last someone finds a long heavy piece of wood.

The church itself was saved as the fire engine arrived soon afterwards and managed to put out the fire before it spread. They carried out the body of Sir Percival Glyde and laid it on the wet ground. I looked down on his dead face and this was how, for the first and last time, I saw him.

I could not leave the town. There would be a legal enquiry into the accident the next day, which I had to attend, and in any case I had to report back to the police station in Knowlesbury. I returned to the hotel and wrote to Marian, telling her everything that had happened and warning her to keep the news from Laura for the moment. With Sir Percival's death, my hopes of establishing Laura's identity had also died, and I could see no way forward at present.

He must have heard that I was free and on my way back to Welmingham, so he hurried to the church, stealing the keys and locking himself in to prevent anyone coming in and finding him. All he could do was tear the page out of the register and destroy it. If the false record no longer existed, I could produce no evidence to threaten him with. He must have dropped his lamp by accident, which started the fire. Then in his urgency to get out, the lock had become damaged and the key unmoveable.

The next day an envelope with my name on was delivered to the hotel. The letter inside was neither dated nor signed, but before I had read the first sentence, I knew who had written it -- Mrs Catherick.

Sir -- I thought you were my enemy. Now that he is dead, because of you, I consider you my friend. To thank you for what you have done, I will now tell you the things you wanted to know about my private life.

Twenty-three years ago I was a beautiful young woman living in Welmingham, married to a fool of a husband. I also knew a gentleman -- I shall not call him by his name. Why should I? It was not his own. I was born with expensive tastes. This man gave me expensive presents. Naturally he wanted something in return -- all men do. And what did he want? Just a little thing. The key to the church vestry, when my husband's back was turned. I liked my presents, so I got him the key. I watched him in the vestry without his knowing, and saw what he was doing. I did not know then how serious a crime it was. I said I would not tell anyone about the marriage he had added to the register if he told me about his private life. He agreed -- why, you will see in a moment.

He said that he only found out that his parents were not married after his mother's death. His father confessed to it and promised to do what he could for his son. But he died having done nothing. The son came to England and took possession of the property. There was no one to say he could not. In fact, the right person to claim the property was a distant relation away at sea. However, to borrow money on the property, he needed a certificate of his parents' marriage. This was a problem -- a problem which brought him to Welmingham.

However, when he saw there was a small space at the bottom of the page in the right year, he changed his plan and took the opportunity to write in the marriage himself. It took him some time, though, to practise the handwriting and to mix the right colour of ink, so that it looked the same.

As his parents had mostly lived abroad and had had no social life in England, who was to say (the priest being dead) that a private marriage had not taken place at Welmingham church? His plan was to tear out a page from the marriage register in the year before his birth and destroy it. Then he would tell his lawyers in London to get the necessary certificate, innocently referring them to the date on the page that was gone. At least no one could say that his parents were not married.

After my husband caught me talking secretly to him and after their fight together, I asked my fine gentleman to clear my name and to say there had been nothing between us. But he refused. He wanted everyone to believe something false, so that they would never suspect the truth. He then told me that the punishment for his crime, and anyone who helped him, was life in prison. He frightened me! If I spoke out, I was just as lost as he was. He then agreed to make me a yearly payment if I said nothing and stayed in Welmingham, where he could always find me and where there was no danger of my making friends and talking. This was hard, but I accepted.

Many years later, when my daughter was with me at home, I received a letter from him which made me very angry. I lost control of myself and said, in her presence, that "I could destroy him if I let out his secret". Then one day he came to our house and called her a fool. Immediately she shouted, "Ask for my pardon, now, or I'll let out your secret and destroy your life. "My own words! He went white. Then he swore at us. It ended, as you know, by his shutting her up in an asylum. I tried to tell him she knew nothing. But he did not believe me. My daughter knew that she had frightened him and that he was responsible for shutting her up because he believed she knew his secret. That's why she hated him. But she never to her dying day knew what his secret actually was.

I will end by saying that you insult me if you think my husband was not my daughter's father. Please do not ask further questions about that. To protect myself, I mention no names in this letter, nor do I sign it.