There was a broken edge to his words that I barely recognized: this wasn’t a side of Nathan that I saw very often, or really knew how to handle. He was usually the calm, collected one, and when he couldn’t fix something, he stepped back and found another approach. He wasn’t the one who fell apart. That didn’t mean he wasn’t allowed: it just meant that when it happened, I wasn’t going to interfere.

“And then there she was! Different, but we’re all different now, aren’t we? We went through the broken doors. That’s how you turn yourself into a monster.” Nathan sighed, kissing the top of my head before he continued: “She opened them as wide as she could and she told me it was all right to look through and see what was on the other side. She said it was what I’d have to do if I wanted to catch up with you, since you’d been born on the other side of those doors. Sally Mitchell never saw them open, but you’ve never seen them closed.”

I tilted my head back, frowning up at him. “I don’t understand.”

“That’s all right. I don’t either, not really.” Nathan sighed. “Mom left me because she had to. She did what she felt was right, and she did it to protect me. But I think sometimes… I think that before Tansy disappeared, she thought her children were invincible. You, me, Adam, Tansy—we couldn’t be killed, because she was looking at everything through the filter of that damn children’s book. She’s shaped her image of the world around someone else’s fantasy.”

I couldn’t stop myself. “Why?”

“Because it’s easier. It’s so much easier to say, ‘This is a story, and there are heroes and villains, and there’s an ending, and when we get there the book will close and we’ll all live happily ever after.’ ” Nathan kissed my head again. “Mom is… her mind works in strange ways. It always has. Dad used to try to explain it to me, after she left us, when I was so sad I didn’t feel like I could get out of bed in the morning. He said she knew she wasn’t always the best with morals and ethics and other things that most people thought were important, because for her, the science—the knowledge—always came first. But she didn’t like hurting people. So sometimes she would fall back to what she saw as a safe place, and she’d retreat to Simone’s book, because in Simone’s book, opening the broken doors always resulted in good things. It always brought the children and the monsters back together.”

“It sounds like maybe your mom needs to see my therapist.” Dr. Morrison was probably dead or in quarantine somewhere. The idea didn’t bother me much.

Nathan pulled away enough to shoot me an amused look. “You hated your therapist,” he said.

“Yeah, but that doesn’t mean she doesn’t need someone to talk to. You’re her son. Adam is, too. I’m…” I paused before admitting, “I don’t really know what I am. I’m not her daughter—which is good, because it would make marrying you sort of creepy—but she thinks I am, and that’s weird. None of us are good for her to talk to. Maybe talking to someone else would help.”

“Maybe,” Nathan allowed. He sighed again. “This hasn’t been easy for any of us, has it? I found my mother but don’t have the time to stop and deal with it emotionally. You lost your whole world.”

“Not my whole world,” I corrected, and took his hand. We sat that way for a while, not saying anything, before I had to go and open my big mouth and ruin everything. “Sometimes I feel like your mom doesn’t know what to do with me. I’m the expendable one.”

Nathan was quiet for a long moment before he said, “I wish I could say you were wrong. But when you disappeared, she said we couldn’t try to rescue you, because it was too dangerous. To be fair, though, she said the same thing about Tansy. I think we’re all expendable to her. We’re all part of the story, and the story needs to be finished more than she needs to be kind.”

That was almost reassuring. It was always nice to know that I was being threatened by a force of nature, and not by someone who actually disliked me for any personal reason. Following that thought to its logical conclusion brought me crashing back down to earth. I sat up a little straighter, the mixed slush of terror and fury beginning to boil in my belly once more, and asked, “What are we going to do about Dr. Banks?”

To Nathan’s credit, he followed my change of subjects without hesitation. “I don’t think he’s going to leave here alive, if that’s what you’re asking. He’s told us too much, and he’s taken too much away. Mom doesn’t forgive easily. Once you overstep your bounds with her, you’re doomed.”

“And USAMRIID wouldn’t have let him come here if they were too concerned with getting him back,” I said slowly. “He said he could give Tansy back.”

“Are you sure we believe him? I think digging the tapeworm out of her brain to make Anna is going to have done a lot of damage, and he has plenty of reasons to lie to us. I hate to say this, but maybe it would be better to let her go.”

“No.” My response was immediate, visceral, and nonnegotiable. “We’re not letting her go. We don’t even know that she’s that messed up. Fang and Daisy took a sample when they had my skull sliced open for the surgery. Sherman did the same thing, even if he was less gentle about it.” His cruder operation had left a scar on the back of my head that was going to be there for the rest of my life. One more thing to hate him for, assuming I was keeping a running list. “Your mom said Dr. Banks must have used her primary segment, but couldn’t he have cultivated a new primary segment in a Petri dish or something? The primary segment is what latches on to the circulatory system in the brain and feeds the rest of the body. I mean, you could dig it out, but… wouldn’t that be a whole lot of work, and maybe dangerous for the implant, when you could just grow a new one?”