Symbiont

by Mira Grant

  “So everybody dies, or everybody lives,” I concluded. “Why would that seem like a good idea? Aren’t the antiparasitics supposed to, um, clear out the old worms so SymboGen can keep selling new ones to people?” The idea was suddenly repellent to me. Every time I’d discussed antiparasitics in the past—even demanded them, only a few hours before—it had been with the idea that they would improve the quality of a person’s life. As I was forced to reconsider what made a person, they suddenly looked like murder.

  You’re adjusting to this too fast, murmured my thoughts.

  But I wasn’t adjusting too fast: not really. I had known the truth for a while, allowing it to integrate itself with my deeper thinking, like it was a second tapeworm writhing and knotting its way through the first. I had invaded Sally Mitchell’s mind, and the truth of my origins had invaded mine. Fair was only fair.

  “It doesn’t seem like a good idea,” said Dr. Cale. “If Steven did this, it’s because he was trying to orchestrate the current crisis. I just… I can’t…” Her face fell, allowing honest dismay to leak briefly through her so carefully constructed mask. “It’s bad for stock prices,” she said finally. “It’s going to destroy SymboGen. There’s no way he can recover from this. As soon as people realize that the implants are responsible, he’ll be finished, he’ll be lucky to walk away a free man—and even then, he’ll need to keep his eyes open for the rest of his life, or the family of one of the sleepwalkers will bring that life to a short and brutal end. It doesn’t make sense for Steven to have done this.”

  I frowned. “Is surgery an option? Couldn’t they, you know…” I made a snipping motion with one hand, like it was a pair of scissors. “That’s how you got Adam out of you, right? You had your assistants cut you open.”

  “We don’t have the facilities or the personnel for that sort of mass surgical intervention,” said Dr. Cale. “That also assumes the worms have not yet started to migrate. You’re so integrated with Sally Mitchell’s brain tissue at this point that we couldn’t remove you even if we wanted to. There’s a point past which there is no going back.”

  “That means that all the sleepwalkers are past saving, surgically or otherwise,” added Nathan. “That ship has sailed.”

  “Oh,” I said quietly. “So, um. How much time would it take for someone to modify the design on the implants? I know I’m… I mean my implant was… I mean I’m one of the older generations. I probably don’t have that much human DNA in me.”

  “Given the generational cycle of D. symbogenesis—it’s compacted down to a matter of months when you’re working in a lab environment, outside of a human host—you could increase the human DNA to this level in two years, give or take a few quality control tests. Maybe a little longer, if you wanted to be absolutely sure of stability. Maybe a little less time, if you weren’t worried about side effects,” said Dr. Cale.

  “Side effects like growing through the muscle tissue of your host and eventually trying to take them over?” I ventured. “I mean, apparently I did that too, but not until after Sally had her accident, when it was all a matter of survival. If I hadn’t taken over, we would both have died.”

  “Yes, those would be considered side effects,” said Dr. Cale.

  “So, um, how long ago did Sherman go all AWOL on you?” I frowned a little. “He’s been at SymboGen for as long as I can remember, and he had friends in the science department—Dr. Sanjiv and Dr. McGillis at the very least. Um, they used to do my MRIs, so I know they knew what I was, and Dr. Sanjiv was also I think in the genetics department? And Dr. McGillis was all about internal medicine, and anyway, I think he could probably have done it.”

  “Sherman?” asked Nathan.

  “You remember how I had those two handlers at SymboGen? The really pretty, really chilly lady and the tall dude who always had a tan even though he mostly worked underground?”

  Nathan nodded. “Yes. He… ah, well, he tried to convince me to go out to dinner with him once.” He rubbed the back of his neck with one hand. “This was after I had told him I was there to pick you up, mind. He seemed to think that my having dinner with him would make me a better boyfriend for you. Fortunately, you showed up about that time, and he didn’t have the chance to press the issue.”

  “That sounds like Sherman,” said Dr. Cale. There was a bleak note in her voice, like she was making light commentary to keep herself from starting to scream. “He used to say that gender was a construct of the body and the mind, and that since his mind was a hermaphroditic worm dreaming of being a gendered biped, he felt no reason to restrict himself any further.”

  “But when did he leave here?” I pressed. I vaguely remembered Tansy saying something about him disappearing from the lab six months before I had—before Sally had—before the accident, but I wanted to be sure. So much had happened during my brief visit to SymboGen that I no longer completely trusted my recollections. “Tansy said something about my accident…”

  “Yes,” said Dr. Cale wearily. “He left here about six months before Sally Mitchell lost control of her car. I had just finished doing my monthly check on the chimera—”

  “The what?” interrupted Nathan.

  “Adam, Tansy, and Sherman: my chimera,” said Dr. Cale. “People—and they are people, anything that can think and communicate and tell you what it prefers to be called is a person, regardless of species or origin—who were created by combining multiple organisms. It’s a medical term, usually, for beings that have multiple distinct types of DNA in their bodies. It’s frequently used for people who absorbed their twins while they were in the womb, to give a common example. In mythology, a chimera is a creature made up from bits and pieces of different animals. I use it for the hybrids. It sounds less… judgmental than ‘parasite’ or even ‘symbiont.’ ”

  “So that means me too, now,” I said quietly. Dr. Cale glanced at me, looking almost guilty. I shrugged. “It’s okay. I like it. And you’re right—it’s a better word than ‘hybrid,’ or ‘freak,’ and those were really the only things that I was coming up with. What kind of check were you doing?”

  “Making sure there was no tissue rejection or complication, that their human immune systems hadn’t suddenly started attacking their tapeworm bodies as invaders, that there was no mismatch between the neural network and the activity coming from the worm—all fairly standard.” Dr. Cale must have read the dawning disgust in my expression, because she hastened to add, “Dr. Banks was performing very similar tests on you. Chave confirmed it for me, starting when you were brought back to SymboGen for neural mapping. I would have intervened much sooner if I thought that you were in any danger of rejection.”

  I wanted to believe her, I really did—I was her tapeworm “daughter,” after all, and I’d been dating her biological son for several years. She had every reason to want to help me stay healthy and psychologically intact. But she wouldn’t meet my eyes, and I had to ask myself whether she’d been viewing me as a true control group: something not to be touched or interfered with, because that would have spoiled her data.

  “So Sherman left right after you gave him a clean bill of health,” I said slowly, trying to select the words to make what I was saying both inoffensive and clear. “Did you say anything like ‘this means you’re stable’ or ‘this proves the interface can sustain itself in the long term’ or ‘yay, you’re not going to melt’?”

  Dr. Cale frowned. “Maybe…”

  Sometimes smart people can be a special kind of stupid. The kind where they know so many facts and are so good at saying “no one would ever do that” that they somehow manage to convince themselves the world is going to care about what they think. It’s like they believe that intelligence alone defines the universe. “So what if he saw that as permission?” I asked. “He left, and he knew what he was, and that humans had created him, and that maybe there was a way to make more like him. And then I happened, and he realized that it could happen naturally. You knew what the signs looked like. So did Dr. Banks. Why wou
ldn’t Sherman?”

  “You think he went to SymboGen specifically to begin engineering the downfall of the human race.” It wasn’t a question, and Dr. Cale didn’t sound horrified when she said it. If anything, she sounded… impressed. Like this was something any parent would absolutely want their son and protégé to think of doing.

  I looked to Nathan, too baffled by her tone to know what to say. Thankfully, he wasn’t siding with her on this one. Expression hardening, he looked at her and asked, “Mom, do you think that what Sal is suggesting is possible?”

  “Possible, yes,” said Dr. Cale. “Probable, given the rest of what we know… oh, yes. Sherman never went to college, for obvious reasons, but all of my chimera children have helped me in the lab as part of their chores. He understands genetics at least as well as your average lab assistant, and probably better than the majority of them. He knew that we were going to have issues when the human population figured out that their implants had the potential to become sapient; he knew there was a chance that the chimera and human races would wind up competing for ownership of the planet. He could very easily have decided this was the appropriate way to approach the problem, and simply put his plans into action once he managed to find a sympathetic ear.”

  “I don’t understand how anyone could think handing their bodies—and their world—over to a different species was a good idea,” I said.

  “Humans have done a lot to damage this world, Sal,” said Dr. Cale. “The idea of keeping our human bodies, which are useful things for manipulating the environment, but replacing their brains with something that might be a little kinder…”

  I stared at her. “We’re tapeworms,” I said. “We’re parasites.”

  “Yes. You don’t kill your hosts on purpose, although you’re more than happy to rewire them to suit your needs. Humans, on the other hand, have a long tradition of killing our hosts. It’s almost a genetic imperative with us.”

  “But we kill the original personality,” I protested.

  “Biology doesn’t care. The genes are still there; the body is still alive,” said Dr. Cale. “I’m not saying Sherman had the right idea by encouraging his people to increase the amount of human DNA in the implants—if it was Sherman; I’ll be able to tell whether he asked them to use any of my research techniques once I’ve had the chance to cross-check this data against the recent specimens that Tansy brought back from Lafayette—but I am saying I understand how he could have talked other people into going along with him.”

  “If this was Sherman, how is he activating the sleepwalkers?” asked Nathan. “What mechanism is he using?”

  “I don’t know yet,” said Dr. Cale. “But I will. Trust me on that. I will.”

  “My head hurts,” I said, putting one hand against my temple. It felt surprisingly fragile now, like I was carrying around my brain and my body in an eggshell, one that could smash open and spill me on the floor at any moment. “I want to go home.”

  Dr. Cale actually looked alarmed. “I’m sorry, but I can’t let you do that.”

  “What?” I lowered my hand, staring at her. “What do you mean, you can’t let me do that? I want to go home. Why is that so difficult?”

  “Because SymboGen’s security is going to be looking for you by now, and Tansy still isn’t back,” said Dr. Cale. “It’s not safe for you to go out without someone to keep an eye on you. The sleepwalker activity in San Francisco is rather extreme right now.” She shot a meaningful look to Nathan, who frowned and looked away.

  I scowled at the both of them. “You didn’t mention my—I mean, Sally’s father, who’s probably looking for me by now, especially if that treatment we suggested for Joyce didn’t work, and did I mention that I don’t care what you think? I want to go home. Beverly and Minnie need to be let out, or they’re going to destroy the apartment.”

  “Beverly and Minnie?” asked Dr. Cale blankly.

  “Our dogs,” said Nathan. “Sal’s right, Mom. Even if it’s not safe for us to stay in the apartment anymore, we can’t leave the dogs alone there. They’ll run out of food and water, and I’m not willing to do that to them.”

  Beverly and Minnie were rescues, casualties of the same epidemic that had claimed so many human lives. Beverly’s owner was last seen in the hospital, sunk deep in the coma that claimed many sleepwalkers in the early stages of their illness. He’d been hospitalized when he lost consciousness, and he’d still been there when vital services began to collapse. I didn’t know whether he had died or woken up and shambled off to join his fellows, but either way, I wasn’t giving back his dog. Minnie’s situation was similarly tragic, and made slightly worse by the fact that Nathan and I had known her owners. Katherine had become sick and had killed her wife, Devi, who used to work with Nathan at San Francisco City Hospital.

  Whether she was still trapped in the hospital or loose on the streets of San Francisco, I hoped that Katherine didn’t remember anything about the woman she used to be: I hoped her colonizing worm had wiped her original identity cleanly away. No one should have to live remembering that they murdered their own wife.

  I shook my head vigorously. “I didn’t come here to be your prisoner, and I’m not going to stay if I’m not allowed to come and go when I want. I’ve already been through that with the Mitchells. If you’re not willing to let me go and take care of my dogs, I’m going to leave anyway, and I’m not going to come back.”

  Dr. Cale sighed, sagging in her chair. “Do you understand that this is all about your well-being?” she asked. “It’s not safe out there, and from what I’ve been able to determine so far from the data you retrieved from SymboGen, it’s not going to get safer anytime soon. Things are going to get much worse before they get better.”

  “How much worse?” asked Nathan.

  “Ten percent human DNA,” said Dr. Cale grimly. “That’s an apocalypse number.”

  “How soon?” asked Nathan.

  Dr. Cale hesitated before she said, “I don’t know.”

  “Then why don’t we compromise?” I asked. They both turned to me. “Nathan and I will go and get the dogs. We’ll be careful, and we won’t let ourselves get arrested or eaten or anything, but we’ll go, because we have to go. And then we’ll come back here. You won’t keep us prisoner, and we’ll be here willingly for as long as it takes to find an answer that doesn’t end up in the extinction of the human race. But you have to show that you can let us go before we’re going to agree to do that. You have to show that you’re playing fair.”

  “I don’t see—” began Dr. Cale.

  “Mom,” said Nathan. His voice was soft, but it stopped her dead. She looked at him for a moment, tilting her chin up to compensate for the difference in their heights. Then she sighed.

  “I don’t like this,” she said. “You’re my son, and she’s virtually my daughter, in more ways than one, and I don’t like this at all. I’m supposed to keep you safe. It’s my job. How am I supposed to be a good mother to you if you won’t let me do my job?”

  “How are you supposed to be a good mother if you’re choosing to be a jailer instead?” asked Nathan.

  Dr. Cale didn’t have an answer for that. She just looked away, and said nothing at all.

  Half an hour later, Nathan and I were in the front seat of his car, driving toward San Francisco faster than I liked, with strict instructions to turn around and return to the lab if we encountered anything that seemed threatening or out of place. “I can’t lose you,” was what Dr. Cale had said, as she watched us head for the bowling alley door. Adam was nowhere to be seen. I had felt—and still felt—guilty and glad at the same time. I didn’t want him to see me go. Not with Tansy missing, not when there was so much reason for him to question whether I would ever be coming back.

  I really hoped we’d be coming back.

  Nathan’s attention was fixed almost completely on the road, and my attention was focused on keeping my eyes closed and my shoulders relaxed. If I allowed myself to think too hard about how fast
we were going, I would lose my nerve and start screaming for him to slow down, slow down before he got us both killed. It was sort of funny, in an awful kind of way: I existed because Sally Mitchell had suffered a seizure and lost control of her car, freeing the way for me to colonize her brain. But the therapy—or I guess the experiment in psychological conditioning pretending to be therapy—that I’d been required to go through as part of my “recovery” had left me with a phobia of cars and car crashes that bordered on crippling. Had Sally been the one left in our shared body when all was said and done, she would probably have gotten her license back by now. I’d been essentially an infant, and any infant barraged with an unending stream of automotive horror stories would have developed a phobia just like mine.

  Thinking about that made it even harder not to be angry with Dr. Cale, and with SymboGen, for the way they’d allowed me to be handled. I wasn’t a control group. I wasn’t an experiment. I was a person, and they shouldn’t have psychologically damaged me just to see what would happen if they did. Dr. Cale knew what I was from the moment I opened my eyes. She shouldn’t have allowed me to be twisted into something that I was never going to be.

  She shouldn’t have let them try so hard to turn me into a human.

  “We’re approaching the end of the bridge, Sal,” said Nathan, using the light, almost aggressively conversational tone he always affected when he was trying to keep me from panicking during a stressful car ride. I was grateful for that consideration, even as I resented it. My boyfriend shouldn’t have been forced to speak to me like I was a child because someone else had taken it upon themselves to give me a phobia I didn’t need to have.