‘They relish what they are doing. They plot, they devise stratagems, they cause as much confusion as they can. They not only pursue a certain quarry, the mysteries and riddles of Sir Thomas, I think they enjoy the killing. They have insufferable arrogance. Satan has set up camp in their souls. In a word, Sir John, they enjoy what they do as much as you do a goblet of claret or a game of hazard or teasing me. To them murder is now part of their lives, a piece in the fabric of their souls. They will continue to murder for profit, to protect themselves but also because they want to. All the more to see us floundering around in the dark. The more we flounder, the more enjoyment we give them.’

Sir John shivered and looked around the tavern. He felt uneasy for the first time ever, a prickling at the back of his neck, a sense of personal danger. Had they been followed? He looked quickly across at Athelstan. The friar was right. Whoever had committed these murders planned them well. If Lady Isabella was not the woman who went to the apothecary’s shop, then who was? And the harlot who had lured Vechey to his doom? And the secret poisoner of Sir Thomas and Master Allingham? Cranston suddenly blinked.

‘You keep saying “they”,’ he said. ‘Why?’

‘There must be more than one. Either that or it’s someone very clever. I did think that someone outside that house was using assassins, professional killers, but that would be too dangerous. You see, the more people you hire to carry out a plot, the greater the danger of betrayal; either through a mistake, or a bribe, or simply by one of your minions being caught red-handed.’

‘And you have no suspects?’

‘No. It could be Sir Richard, it could be Lady Isabella, Buckingham, Father Crispin, even Dame Ermengilde. Who knows? One of the murdered men may have been an assassin.’

Sir John drained his tankard and slammed it down on the table.

‘You know, Athelstan, if it wasn’t for you and your bloody logic, I’d put the entire mystery down to witchcraft. People moving about in the dead of night, poisons being administered in a locked room. How on earth can we resolve it?’