to break up the wooden chests with his hammer and chisel. He took the wool coats from the hook, bundled them up, and held the tip of his candle flame to the bundle. The wool caught fire immediately. He piled wood from the chests on top of the burning wool. Soon there was a merry bonfire, and the smoke caught in his throat.
He looked at Tilly, lying helpless on the floor. He drew his knife. Then, once again, he hesitated.
From the prior's palace, a small door led directly into the chapter house, which itself communicated with the north transept of the cathedral. Merthin and Caris took this route in their search for the source of the scream. The chapter house was empty, and they went into the church. Their single candle was too dim to illuminate the vast interior, but they stood in the centre of the crossing and listened hard.
They heard the click of a latch.
Merthin said: "Who's there?" and was ashamed of the fear that made his voice tremble.
"Brother Thomas," they heard.
The voice came from the south transept. A moment later Thomas moved into the light of their candle. "I thought I heard someone scream," he said.
"So did we. But there's no one here in the church."
"Let's look around."
"What about the novices, and the boys?"
"I told them to go back to sleep."
They passed through the south transept into the monks' cloisters. Once again they saw no one and heard nothing. From here, they followed a passage through the kitchen stores to the hospital. The patients lay in their beds as normal, some sleeping and some moving and groaning in pain - but, Merthin realized after a moment, there were no nuns in the room.
"This is strange," said Caris.
The scream might have come from here, but there was no sign of emergency, or of any kind of disturbance.
They went into the kitchen, which was deserted, as they would have expected.
Thomas sniffed deeply, as if trying to pick up a scent.
Merthin said: "What is it?" He found himself whispering.
"Monks are clean," Thomas murmured in reply. "Someone dirty has been here."
Merthin could not smell anything unusual.
Thomas picked up a cleaver, the kind a cook would use to chop through meat and bones.
They went to the kitchen door. Thomas held up the stump of his left arm in a warning gesture and they halted. There was a faint light in the nuns' cloisters. It seemed to be coming from the recess at the near end. It was the reflected gleam of a distant candle, Merthin guessed. It might be coming from the nuns' refectory, or from the flight of stone steps that led up to their dormitory; or both.
Thomas stepped out of his sandals and went forward, his bare feet making no sound on the flagstones. He melted into the shadows of the cloister. Merthin could just about make him out as he edged towards the recess.
A faint but pungent aroma came to Merthin's nose. It was not the smell of dirty bodies that Thomas had detected in the kitchen, but something quite different and new. A moment later Merthin identified it as smoke.
Thomas must have picked it up too, for he froze in place up against the wall.
Someone unseen gave a grunt of surprise, then a figure stepped out from the recess into the cloister walk, faintly but clearly visible, the weak light outlining the silhouette of a man with some kind of hood covering his entire head and face. The man turned towards the refectory door.
Thomas struck.
The cleaver glinted briefly in the dark, then there was a sickening thud as it sank into the man's body. He gave a shout of terror and pain. As he fell Thomas swung again, and the man's cry turned into a sickening gurgle, then stopped. He hit the stone pavement with a lifeless thump.
Beside Merthin, Caris gasped with horror.
Merthin ran forward. "What's going on?" he cried.
Thomas turned to him, making go-back motions with the cleaver. "Quiet!" he hissed.
The light changed in a heartbeat. Suddenly the cloisters were illuminated with the bright glow of a flame.
Someone came running out of the refectory with a heavy tread. It was a big man carrying a sack in one hand and a blazing torch in the other. He looked like a ghost, until Merthin realized he was wearing a crude hood with holes for the eyes and mouth.
Thomas stepped in front of the running man and raised his cleaver. But he was a moment too late.