Andrew Swanston - The King's Spy

The king was on his feet. ‘That cannot be. The queen’s route has been kept a close secret. Almost no one knows it.’

‘I fear, sir, that the sender of this message knows it.’

The king held out his hand for the text. He read it twice, and sat down. ‘I cannot accept this without further evidence. Tobias Rush is a loyal and trusted servant. To be told now that he is a traitor is beyond comprehension. And you, Master Hill, after your theatrical display, what am I to make of you?’

‘I can understand your majesty’s dilemma. I wish that the keyword had occurred to me before. That it came to mind only on my way here this morning is indeed strange. I blame myself for not thinking of it sooner.’

‘And what is this keyword which eluded you for so long, Master Hill?’

‘Your majesty will recall that the keyword to the first inter cepted message was PARIS. This one turned out to be the same letters, but backwards. SIRAP. Messages go back and forth. So did the keywords.’

‘Could you be mistaken as to the sender’s name?’

‘No, sir. The sender’s name is Rush.’

The king closed his eyes. ‘It is beyond belief.’

‘If I may, your majesty,’ went on Thomas, ‘there are other things of which you should be aware. I am quite sure that Erasmus Pole was not murdered in Brasenose Lane, but his body dumped there after he had been killed somewhere else. Why would the murderer do that other than to conceal his motive? The murderer of Abraham Fletcher was looking for something, and tortured him when he could not find it. He could not find it because I had it. It was the first message. My room was also searched but, fortunately, the message was not found. Master Rush arranged for me to be imprisoned in an effort to get rid of me, and to retrieve the message. Again, we were fortunate. It was hidden, and, in your absence, the queen graciously commanded my release. Without her intervention, I would certainly be dead. Your majesty will also have heard that Lady Romilly, lady-in-waiting to the queen, was cruelly raped and murdered. However, she lived long enough to reveal the identity of the man behind this bestial crime. It was Tobias Rush.’ There was little point in mentioning Fayne. He would be no more than a name to the king, and Thomas had no proof of his association with Rush or his conduct at Newbury. There was more to be done before Francis Fayne faced justice.

‘Merciful God. Tobias Rush, to whom I have entrusted many secrets, and whom I trusted with the queen’s life. Is there more?’ asked the king.

‘Rush knew how I had decrypted the first message. He’s a clever man. He used the Vigenère square again, but in a very short message with no repetitions or numbers, and with nulls — that is, extra letters inserted in the text to confuse a decrypter. Without the keyword, the message was impregnable. It was only by chance that I guessed it.’

‘Master Rush is one of the very few who knew of our plan for the queen to travel to Exeter from Bristol. He is away now making arrangements.’

‘When does he return, sir?’

‘Tomorrow.’

‘Your majesty, Tobias Rush is ruthless. He must be appre hended before he gets wind of what we know. The queen herself might otherwise be in danger. He would almost certainly have sent a copy of such an important message by more than one carrier.’

‘He will be met by my Lifeguards when he arrives at the city wall. They will escort him here to face his king. Only when I have interrogated him myself will I know for certain whether or not he is a traitor. Meanwhile, Master Hill, you will remain in your rooms. A guard will be posted outside the door. Master Rush’s rooms will be searched. I will send for you if I wish to speak to you further.’

After little sleep and no breakfast, Thomas was tired and hungry. There was no elation at breaking the cipher and proving Rush’s guilt, or relief at his own reprieve. Abraham and Jane were dead. Both had died in agony, both at the hands of Rush. And Jane had been raped by Fayne. The breaking of the message was nothing beside that. He needed to think about them before he could begin to get over his loss. Having scavenged bread and cheese from the college kitchen, he returned to his room, lay on his bed and pictured Jane’s eyes.

He was asleep when the guard threw open the door. ‘Master Hill, the king wishes to see you at once.’ In the bedchamber, Thomas heard nothing. The guard went in and shook him. ‘Master Hill, you must arise, sir. The king has summoned you.’ Thomas struggled awake. Four hours’ sleep felt like four minutes. The guard helped him up. ‘Get dressed, sir. I will take you to the king.’ Please God, thought Thomas, no more ciphers. I haven’t the strength.

On a table beside the king stood a small iron box. It had been forced open. ‘This box was found concealed behind a wall in Master Rush’s rooms,’ the king told him in a quiet voice. ‘It contained these two documents.’ He handed them to Thomas, who unrolled one. On it had been written a column of letter sequences. The sequences were five or six letters in length. He put it down and unrolled the other one. On this was a column of numbers, which did not correspond to the number codes used in the first message. In both cases, Thomas recognized the hand of Tobias Rush.

‘What do you make of them, Master Hill?’ asked the king.

‘The alphabetical list is probably an encrypted list of keywords, sir, and the numerical list a list of codewords. They are both written in Tobias Rush’s hand.’

‘Of that I am aware. Can you decrypt them?’

‘As we already know some of the number codes being used, and we know PARIS is one keyword, it should not be difficult, your majesty.’

‘In that case, start work at once, and bring me the results the moment you have them.’

Taking the two documents, Thomas bowed and left. Ciphers for sleep. A poor trade.

He started with the letters. If he was right about the numbers, they were less important. He looked at the list.

If they were keywords, one of them would be PARIS. Only two of the sequences had five letters — QCUMX and NKOES — one of which would be it. It did not take Thomas long to find out which. He very quickly established that each letter of the plain word was encrypted by a letter of the alphabet the same number of places after it as its position in the word. So in PARIS, P became Q, A became C, R became U, I became M, and S became X. He soon had the list in plain text.

Keywords to Vigenère squares or alphabetic shifts, which would be used in turn, replies using the same words backwards. After MILAN, the sender would go back to LONDON.

The numbers also submitted without a fight. The man who had devised these ciphers was not the most imaginative encrypter that Thomas had ever faced. He had disguised the numbers in a similar way to the letters, only backwards. He had used the numbers one to nine, and returned to one after nine. There were ten further numbers which Thomas decrypted, but could not, without a context, put names to. And there, for all to see, was 775, now revealed to be Tobias Rush. The senders of messages would have committed to memory the names represented by each number.

On receiving the decrypted lists, the king said only that Thomas would no longer be under guard, that he might leave Christ Church as he wished, and that arrangements would be made to escort him back to Romsey. Until then Thomas must stay in Oxford in case of further developments. He now knew with certainty that one of his most trusted advisers had been sending and receiving encrypted messages on behalf of his enemies, and that he would have had access to all incoming and outgoing messages from the man who had replaced Thomas.