Strangers

studies here were after the fact. I'm essentially a… well, a fire marshal, a guy who came in after the blaze to sift through the ashes and figure out what happened. The potential for possession or infection - if it ever existed - was at the beginning, in the first hours, not later."
        "How can I be sure of that?" Leland asked, staring at him coldly.
        "But under these lab conditions, with safety precautions-"
        "We're dealing with the unknown, Doctor. We can't foresee every problem that might arise. That's the very nature of the unknown. And you can't take precautions against something you can't foresee."
        Bennell shook his head violently in denial of the very possibility. "No, no, no. Oh, no."
        "If you think I'm exaggerating my concern just to irritate you," Leland said, "then you might ask yourself why Lieutenant Horner sat in that chair so alertly during our long conversation. After all, as you know, he's an expert in polygraphs, and he could have gone and repaired yours while you and I talked. But I didn't want to be in a room with you alone, Doctor Bennell. Not alone. No way."
        Blinking, Bennell said, "You mean, because I might've somehow…"
        Leland nodded. "Because if you have been changed, then you might have been able to change me, too, by some process I can't even begin to imagine. Alone, you might have used the opportunity to attack me, infect me, arrange for me to be possessed, pour the human spirit out of me and pour something else in." Leland shuddered. "Hell, I don't know how to put it best, but we both know what I mean."
        "We even wondered if two of us were enough to insure our safety," Lieutenant Horner said, his voice rumbling through the low-ceilinged room and vibrating vaguely in the metal walls. "I kept a close eye on you, Doctor. You didn't notice my hand was always near my revolver."
        Bennell was too astonished to speak.
        Leland said, "Doctor, you may think I'm a suspicious bastard who's too quick on the trigger, an unregenerate xenophobic fascist. But I've been put in charge of this not merely to keep the truth from the public but also to protect them, and it's part of my job to think of the worst and then to act as if it will inevitably happen."
        "Jesus H. Christ!" Bennell said. "You're total, off-the-wall paranoids, both of you!"
        "I'd expect you to react that way," Leland told him, "whether or not you're still a full-fledged member of the human race." To Horner he said, "Let's go. You have a polygraph to repair."
        Horner went out into The Hub, and Leland started after him.
        Bennell said, "Wait, wait. Please."
        Leland looked back at the pale, black-bearded man.
        "All right, Colonel. Okay. Maybe I can see why you've got to be suspicious, why it's just part of your job. It's crazy nonetheless. There's no chance that I or any of my people could've been… inhabited by something else. No chance. But if you were ready to kill me if I aroused your suspicion, would you also kill everyone working under me if you decided they'd all been taken over?"
        "Without hesitation," Leland said bluntly.
        "But if I and my people could've been changed, if that much was possible - and it isn't possible - then don't you realize that the entire staff in Thunder Hill could've been changed, too? Not just the people who know what's in that cavern, but everyone, military as well as civilians, all the way up to and including General Alvarado."
        "Well, sure," Leland said. "I realize that."
        "And you'd be willing to kill everyone in the facility?"
        "Yes."
        "Jesus!"
        "If you've decided to split," Leland said, "you can forget about leaving for the duration. Eighteen months ago, looking ahead to this possibility, I secretly had a special program entered into VIGILANT, the security system. At my direction, VIGILANT can institute a new policy that makes it impossible for anyone to leave Thunder Hill without a special code. I'm the only one with the code, of course."
        Bennell's posture was the essence of indignation and righteous outrage. "You mean, you'd imprison us out of some misguided…" He fell silent as the truth hit him. Then: "My God, you wouldn't have told me this if you hadn't already activated VIGILANT'S new program."
        "That's right," Leland said. "When I came in, I identified myself with my left hand on the ID plate, instead