expression at all to his inclinations. That the satisfaction of sexual perversion in many ways resembles addiction to drugs. This is borne out by foreign examples. A person who is a sexual pervert can behave for year after year as an exhibitionist or a Peeping Tom and in that way find an outlet for his sex urge. But if that person, on a sudden impulse, commits a rape or a sex murder, the only way he can get satisfaction in future is to commit .more rapes and more murders.'
'Like the old story about the bear,' Gunvald Larsson said. 'A bear that has once killed a cow, and so on.'
'It's the same with a junkie who wants stronger and stronger drugs the whole time,' Melander said, riffling through the report. 'A junkie who starts off with hashish and then changes to heroin can't go back to hashish because he gets no kick out of it any more. It may be the same sort of thing with a sexual pervert.'
'It sounds sensible,' Kollberg said. 'But elementary.'
'I think it sounds damned unpleasant,' Gunvald Larsson said.
'It's much more unpleasant than that,' Melander said. 'It says here that a person can have lived for many years without giving any noticeable expression to his perverted sex urge, he needn't even have masturbated or looked at dirty pictures, still less have behaved as an exhibitionist or a Peeping Tom. He can simply have sat thinking of different forms of perversion, without actually knowing about it himself, until suddenly a chance impulse triggers off an act of violence. Then he just can't help repeating it, over and over again, with growing ruthlessness and presumably increasing bestiality.'
'Rather like Jack the Ripper,' Gunvald Larsson said.
'What about the impulse?' Kollberg asked.
'It can be triggered off by all kinds of things—a chance situation, a state of mental weakness, illness, liquor, drugs. If this view of crime is admissible, then there are no clues to the criminal in his own past. The police registers are useless, the same as the case histories of hospitals and doctors. The person in question just isn't there. And once he has started raping or killing, he can't stop. He's also incapable of giving himself up or of controlling his own actions.'
Melander sat in silence for a moment. Then he tapped with his knuckles on the xeroxed report and said:
'There's something in this that fits our case horribly well.'
'I imagine there are dozens of other explanations,' Gunvald Larsson said irritably. 'It might be a stranger, for instance, a foreigner just passing through. It might even be two different murderers; what happened in Tanto Park was perhaps a murder done on the spur of the moment—an impulse caused by the publicity around the first one.'
'There's a lot against that line of reasoning,' Melander said. 'Knowledge of the locality, the somnambulant certainty with which the murder was carried out, the choice of time and place, the absurd fact that after two murders and seven days of search we haven't found a single suspect worth mentioning. Unless we count that man Eriksson. And there's a detail that rather discounts the theory of an impulse murder: in both cases the girl's pants were missing. That information has not been given out to the press.'
'I imagine there are other explanations all the same,' Gunvald Larsson said surlily.
'I'm afraid that's wishful thinking,' Melander said, lighting his pipe.
'Yes,' Kollberg said, rousing himself. 'It may be wishful thinking, Gunvald, but I do hope you're right. Otherwise…'
'Otherwise,' Melander said, 'we have nothing at all. The only thing that can lead us to the murderer is to catch him red-handed next time. Or…'
Kollberg and Larsson each completed the thought and arrived at the same unpleasant conclusion.
'Or for him to repeat the murder over and over again with the same sleepwalking certainty until his luck gives out and we catch him,' Melander said.
'What else does it say there?' Kollberg asked.
'The usual rigmarole. A whole lot of contradictory speculations. He can be oversexed or undersexed—the latter seems to be the most probable. But there are also examples of the reverse.'
Putting down the report Melander said:
'Has it occurred to you that even if we saw him standing here in front of us we have no proof that he committed these two murders. The only material we have is some very dubious footprints in Tanto Park. And the only thing actually proving that the person we're after is a man, is a few spermatozoa on the ground near the girl's body, again in Tanto Park.'
'And if he's not in our records we wouldn't even be helped by a full set of fingerprints,' Kollberg said.
'Exactly,' Melander said.
'But we have a witness,' Gunvald Larsson said. 'The mugger saw him.'
'If only we could rely on that,' Melander said.
'Couldn't you say one little tiny thing to cheer us up?' Kollberg asked.
Melander made no answer and they lapsed into silence. In the room next door they heard the telephones ring and Ronn and someone else answer.
'What did you think of that girl?' Gunvald Larsson asked suddenly.
'I liked her,' Kollberg said.
At the same instant yet another unpleasant thought occurred to him. He knew whom Lisbeth Hedvig Maria Karlstrom had reminded him of. Not his wife, far from it. She reminded him in an ominous way of a person whom he had never met during her lifetime but who had governed his thoughts and actions long after she was dead. He had seen her only once, in the mortuary at Motala on a summer's day three years ago.
He shook himself, ill at ease.
A quarter of an hour later Martin Beck walked in with the ticket.
19
'WHAT'S THAT?' Kollberg asked.
'A ticker,' Martin Beck replied.
Kollberg looked at the crumpled ticket lying in front of him on the desk.
'A subway ticket,' he said. 'So what? If you want your traveling expenses reimbursed you must go to the cashier's office.'
'Bosse, our three-year-old witness, got it from a man that he and Annika met in Tanto Park just before she died,' Martin Beck said.
Melander shut the door of the filing cabinet and came up to them. Kollberg turned his head and stared at Martin Beck.
'Just before the man strangled her, you mean,' he said.
'Maybe. The question is: What can we get out of this ticket?'
'Fingerprints, perhaps,' Kollberg said. Melander leaned forward, muttering, while he studied the ticket.
'Possible but hardly probable,' Martin Beck said. 'First of all the person who tore it off the block touched it, then whoever gave it to the boy must have touched it, I grant you, but the boy has had it in his pocket since Monday together with snails and God knows what, and to my shame I've touched it too. Apart from that, it's crumpled and fluffy. But we'll try, of course. But look at the punch holes first.'
'I've already looked,' Kollberg said. 'It's punched at 1.30 P.M. on the twelfth, it doesn't say which month. That can mean…'
He broke off and all three thought what it might mean. Melander was the one to speak.
'These one-krona tickets, type 100, are used only within the actual city limits,' he said. 'It may be possible to find out when and where it was sold. There are two other numbers on it.'
'Ring Stockholm Tramways,' Kollberg said.
'It's called Stockholm Local Transport now,' Melander said.
'I know. But the uniform buttons still have ST on them. I suppose they can't afford to make new ones. How the hell is that possible when it costs a krona to go from Gamla Stan to Slussen—the next station? What does a button cost?'
Melander was already on his way into the next room. The ticket still lay on the desk, presumably he had photographed it in his mind with serial number and everything. They heard him lift the receiver and dial a number.
'Did the boy say anything else?' Kollberg asked.
