“Well, I hope the pithos was helpful,” Christopher said, shoving his hands into the pockets of his coat. “I still can’t figure out why anyone would want an object that picks up runes and pops them onto someone else.”

“What are you talking about?” Matthew often felt he’d missed something when he was talking to Christopher about his experiments, but this was even more confusing than usual.

“Well,” said Christopher, “if you were a Shadowhunter, you could just draw your runes on yourself, and if you weren’t, you couldn’t have runes at all without becoming Forsaken—”

“Yes, yes, but what are you talking about?”

Christopher sighed. “Matthew, I know it was very late when you came to Grosvenor Square last night, but you must listen when I explain things. It’s not all boring trivia, you know.”

A faint spark of dread flared in Matthew’s stomach. “I didn’t come by the house last night.”

“You did, though,” Christopher insisted, blinking in puzzlement. “You told me that James needed the stele, so I gave it to you.”

A spike of ice pierced Matthew’s stomach. He recalled dropping Lucie off the night before and returning to his flat to spend the rest of the night drinking with Oscar by the fire. If he’d made a surprise visit to his father’s lab at some point in the small hours, he was sure he’d remember it.

“Christopher, I don’t know who you gave the stele to last night,” he said urgently, “but it wasn’t me.”

Christopher went pale. “I don’t understand. It was you, it looked just like you. If it wasn’t you… oh, God, who did I give the stele to? And to what purpose?”

Thomas struggled for breath. The weight of the Sword spread through his chest, and it was more than weight, it was pain—a dozen, a thousand small needles stabbing and dragging at his skin. Words spilled from his mouth, uncontrolled and unpremeditated: he understood now the way in which Maellartach made it impossible to hold back the truth. “No,” he gasped. “I did not kill Lilian Highsmith.”

Charlotte exhaled with relief. The Inquisitor muttered something in a furious tone; if Alastair made a sound, Thomas couldn’t hear it.

As though he were asking Thomas about his breakfast, Will said, “Did you murder Basil Pounceby? Or Filomena di Angelo? Or Elias Carstairs?”

Thomas was prepared for the pain this time. It came from resistance, he thought. From pressing back against the Sword’s urging. He let himself relax, let the words come without fighting them. “No. I am a warrior. But I am not a murderer.”

Will jerked his thumb in the direction of Alastair. “Have you seen that fellow murder any Shadowhunters? Alastair, I mean. He commit any murders to your knowledge? Amos Gladstone, maybe?”

“Excuse me,” said Alastair, looking horrified.