“I didn’t—I don’t—I never have,” said Harrow, “and—I know.”
“You would have killed me.”
“Or vice versa.”
This surprised her into silence. The wavelets sploshed gently at the tiled edges of the pool. Gideon kicked off the bottom and fluttered her feet back and forth, bobbing, her shirt billowing out with water.
“Okay,” she said eventually. “Question time. Who did all the murders?”
“Nav.”
“I mean it. What’s happening? Is Canaan House haunted, or what? What—who—killed the Fourth and the Fifth?”
Her necromancer also pulled her feet up from the bottom and floated, momentarily, chin-deep in green salt water. Her eyes were narrowed in thought. “I can’t say,” she said. “Sorry. That’s not a fruitful line of inquiry. We are being pursued by revenants, or it’s all part of the challenge, or one, or more, of us is picking off the others. The murders of the Fifth and the Fourth may be connected, or not. The bone fragments found in everyone’s wounds don’t match, naturally—but I believe their very particle formation points to the same type of necromantic construction, no matter what Sextus says about topological resonance and skeletal archetype theory…”
“Harrow, don’t make me drown myself.”
“My conclusion: if the murders are linked and if some adept, rather than a revenant force or the facility itself, is behind the construct you saw—then it is one of us,” said Harrow. “We’re the only living beings in Canaan House. That means the suspect list is the Tridentarii; Sextus; Octakiseron; the Second; or myself. And I haven’t discounted Teacher and the priests. Septimus has something of an alibi—”
“Yes, being nearly dead,” said Gideon.
Harrowhark said, rather grudgingly: “I’ve downgraded her in some respects. Logically, judging by ability, and mind, and the facility to combine both in service to an end, it’s Palamedes Sextus and his cavalier.” She shook her head as Gideon opened her mouth to protest. “No, I realise neither has, as you might put it, a fucking motive. A logical conclusion is worth very little if I don’t have all the facts. Then there’s Teacher—and the Lyctor laboratories—and the rules. Why those theorems? What powers them? Why was the Fourth cavalier killed, but you left alive?”
These were all questions that Gideon had privately asked the dead of night many times since Jeannemary had died. She let her shoulders slide back into the water until it was cold up to the backs of her ears, staring at the single fluorescing bar that swung above the pool. Her body floated, weightless, in a puddle of yellow light. She could have asked Harrow anything: she could have asked about the bomb that had taken Ortus Nigenad’s life instead of hers, or she could have asked about her whole entire existence, why it had happened and for what reason. Instead, she found herself asking: “What do you know about the conditioner pathogen that bumped off all the kids—the one that happened when I was little, before you were born?”
The silence was terrible. It lasted for such a long time that she wondered if Harrow had slyly drowned herself in the interim, until—
“It didn’t happen before I was born,” said the other girl, sounding very unlike herself. “Or at least, that’s not precise enough. It happened before I was even conceived.”
“That’s unwholesomely specific.”
“It’s important. My mother needed to carry a child to term, and that child needed to be a necromancer to fill the role of true heir to the Locked Tomb. But as necromancers themselves, they found the process doubly difficult. We hardly had access to the foetal care technology that the other Houses do. She had tried and failed already. She was getting old. She had one chance, and she couldn’t afford chance.”
Gideon said, “You can’t just control whether or not you’re carrying a necro.”
“Yes, you can,” said Harrow. “If you have the resources, and are willing to pay the price of using them.”
The hairs on the back of Gideon’s neck rose, wetly.
“Harrow,” she said slowly, “by resources, are you saying—”
“Two hundred children,” said Harrowhark tiredly. “From the ages of six weeks to eighteen years. They needed to all die more or less simultaneously, for it to work. My great-aunts measured out the organophosphates after weeks of mathematics. Our House pumped them through the cooling system.”