Iceman by Rex Miller

Geary trailed off into space.
    Jack thought he sounded older, tireder than he remembered him. We're all older and tireder, he thought.
    “So this guy could be ugly, like scarred or deformed, or just emotionally unbalanced and be physically Robert Redford?"
    “Of course. You know what mass murderers look like, they're as likely to be movie-actor handsome as hideously ugly. It could be anything. He could be a cripple, or he has an underdeveloped penis, or he's out of whack in some manner, his sexual dysfunction is so severe he must strike out at these women he wants, punish them or blind them. He could be very good-looking in the conventional sense, but he sees himself as inadequate or repulsive by his own standards."
    “And let's say he's the most dangerous type ... I always get this confused, is he the sociopathic type or the schizzy type?"
    “Jack, that's the paranoid-schizophrenic. You need to look at your DSM-III. It's got all that broken down for you."
    “Your what?"
    “Oh, your Diagnostical Statistical Manual, roman numeral three. And if you can get a three-slash-R. Revised update. Give you the definitions for all the terms."
    “All right. Okay. Now. We're back in Texas or wherever, and we're ugly or we have an infant-sized penis or whatever. When the moon is full we go out and get a woman, force them to go down on us, then we strangle them or stab them with an icepick. Let's say we symbolically blind them or punish them. Right so far?"
    “Right—defacing, Jack. Think DEFACING. That one shot with the icepick to the eye—that's the textbook classic. Keeps them from seeing him, you understand, and he's defacing THEM, too, as well. Get it?"
    “Yeah. All right. Now suddenly we stop. For twenty years we don't kill again. Then, suddenly, another killing. Why do we stop? Why didn't we keep killing? Why did we start up again? Give me some scenarios, can you?"
    “First off, he's not your same killer. He didn't stop. The first factor you can take to the bank is this: NOBODY stops. Serial killers don't stop. Not ever. You're the expert. You tell me. When did you ever hear of a serial killer who stopped?"
    “Zodiac."
    “Hmm?"
    “Zodiac. Dude out in California? We never caught Zodiac. He stopped."
    “No, Jack. He was caught. Or he was killed or he died or was imprisoned. By caught I mean for something completely unrelated. For a theft, let's say, and he goes to jail. He's imprisoned. Well, there would be one scenario. Your man is imprisoned for twenty years. He got out and resumed? Huh?"
    “I wish thieves DID go to jail for twenty years, but that's another story. Yeah, I've been over that ground a little. The mental institutions and all."
    “Sure, could be institutionalized for twenty years. That's one scenario. But you take my meaning. Unless something like that happens, nobody stops. They like to kill too well. Unless they mess up, get too cocksure of their own invincibility, and the coppers take them out of the game, they keep on going. But twenty years, Jack? No, a more likely scenario is that he died, or what might be is he got murdered himself. Violence begets violence. Make your own scenario but keep one factor in mind. Nobody ever stops . You can't count on that happening. These persons are deeply deranged and they kill till they get caught.
    “He's also telling something about himself in the demographic profile of the victims. Look at the age group of the women you just read off to me. Now a younger woman. But that could be so consistent, you see, because HE'S older, so he relates to the victim in a different way. There might be a clue in the victims’ profiles. That's where to begin."
    “Yeah. Listen, Doc, while I've got you. On another subject. I just wanted to get your thinking. I realize this isn't your line, but let's say you got a murderous psycho and he has a child. Genetically, is there any way of determining whether, you know, the kid is going to have any inherited traits, er, ah—"
    Geary took