Before Carole had a chance to issue any prompt, Nessa Perks was straight into her lecture. ‘As I mentioned on the telephone, many people too readily dismiss any possible correlation between Golden Age mystery fiction and the real-life world of contemporary crime. But my extensive researches into the subject have revealed that many of the tropes occurrent in the whodunits of the time can act as relevant comparators.
‘And that is certainly true in the case of Burton St Clair’s death. When broken down into their essential components, in such crimes certain patterns obtain. This kind of murder is almost always domestic, and it always starts with the husband having an affair. Then there are three possible scenarios that can happen. For ease of memorizing them, I refer to the scenarios as “HKW”, “WKM” and “WAMKH”.’
Carole didn’t think it was appropriate to say that she had already had this routine spelled out by Ted Crisp. But she admired how efficiently the Professor’s didactic approach had imprinted all the details on the landlord’s memory.
When that part of the narrative had concluded, Nessa Perks paused long enough for Carole to ask, ‘Had you ever met Burton St Clair before last Tuesday?’
‘Ah, that’s the “FA” question. Predictable enough.’
‘“FA question”?’ Carole echoed.
‘“Former Acquaintance”. Much asked in Golden Age mysteries – and no less in contemporary police enquiries. If two apparently unrelated people turn out to have a shared history, well, that information is obviously of great benefit to any enquiry.’
The Professor was silent, as though the question had been fully answered, so Carole ventured to ask, ‘So, had you?’
‘Had I what?’
‘Had you ever met Burton St Clair before last Tuesday?’
‘No. No, I had not.’
‘And of the three possible scenarios you outlined—’
‘The only three possible scenarios,’ Nessa Perks insisted.
‘Very well. Which one do you think applies in this case?’
‘This is very definitely “MKH”,’ she pronounced.
‘“Mistress Kills Husband”?’
‘Indubitably.’
‘What makes you so sure?’
‘Carole, you take my word for it. That conclusion is the result of an entire career of research.’
‘Right. So maybe you could spell out the details for me?’
‘Of course. The most important factor in my deduction here is the comparative newness of Burton St Clair’s marriage. He had been married to Persephone for less than six months. Now, from my exhaustive reading of Golden Age mysteries, I have extrapolated a set of statistics about the length of time that will elapse before a marriage becomes toxic. As a general rule, husbands and wives do not murder each other until well into their cohabitation. Except in the cases of contested wills or marriages undertaken for the sole purpose of inheritance, staples both of the “Sensation” novel of the late Victorian period, there is very little evidence of homicidal activity during the first six months after the wedding.’
‘The honeymoon period?’ Carole suggested.
‘If you like,’ said the Professor, in a manner that suggested only a non-academic would use such a frivolous expression. ‘Intermarital resentment is something which tends to build up over a period of years rather than months.’
Thinking back to her own failed marriage to David, Carole could not but agree. ‘Have you ever been married?’ she asked suddenly. Nessa Perks seemed such a remote and shrink-wrapped personality; it was hard to imagine her having any normal bodily functions, let alone relationships – and certainly not sex.
‘I did contract an incautious union during my sophomore year,’ came the reply, ‘which four years later, after college, developed into a marriage. It did not last.’ And with that the subject was closed.
‘If you could spell out a little more of your “MKH” theory?’ asked Carole humbly.
‘Of course. As I said, homicidal activity is very rare in the first six months of cohabitation, for which reason I would exclude Persephone St Clair from my primary list of suspects.’
‘But Burton St Clair’s current mistress would be in the frame?’
Professor Vanessa Perks shook her head firmly. ‘No, it wouldn’t be a current mistress.’ Carole wondered what it must be like to go through life with such unshakable certainty that one was always right. ‘No, for a man of Burton St Clair’s age, a new marriage would be a completely new start. A tabula rasa.’ Assuming, incorrectly, that Carole did not understand the Latin expression, she provided a gloss. ‘A blank slate.’
‘Yes, I do know—’
‘So, embarking on a new marriage, Burton St Clair would have ended all other romantic entanglements.’
Not if he has the character Jude has described to me, thought Carole.
‘As a suspect, we are looking therefore for a former mistress.’
‘And her motivation?’
‘In Golden Age mystery fiction, there are only five reasons to commit murder.’ As she must have done in many lectures and seminars, she enumerated them on her fingers. ‘Cover-Up, Revenge, Insanity, Money and Sex. Which fit rather neatly into the mnemonic: “CRIMS”—’
‘Erm,’ Carole interrupted, ‘aren’t there a few other possible motivations for murder? Surely there are also—?’
‘No, there are just the five,’ said the Professor in a voice that brooked no argument. ‘Believe me, I have done a lot of research on the subject. Now, in this case, looking across the CRIMS spectrum, I would say we’re definitely looking at “S”. Sex. Burton St Clair had a complicated emotional route to finding his perfect partner in the form of Persephone. He had a lot of relationships …’
‘He also had a former marriage.’
‘Yes, I know that, Carole.’ This was made to sound like a reprimand. ‘I have obviously done a lot of research on him. And it seems that he was responsible for various infidelities during the period of his first marriage. So I would say definitely what we are looking at here is “RIADBSC” scenario.’
‘“RIADBSC”?’ came the feeble echo from Carole.
‘“Revenge is a dish best served cold”,’ Nessa translated fluently. ‘A very popular scenario with Golden Age mystery writers. An offence is allowed to rankle for a very long time, and finally, when the offendee can take no more pain and humiliation, his or her restraint snaps and the result is inevitably homicide.’ Professor Vanessa Perks sat back and took a sip of Earl Grey, confident that she had produced an unanswerable thesis.
‘Very well,’ said Carole. ‘Sorry if I’m being stupid, but could you tell me how that applies in the current case?’
‘You’re not being stupid,’ said the Professor magnanimously, ‘it’s just that very few people’s brains work at the rate that mine does. This was something which came apparent in high school, and since then it’s just something I’ve had to live with.’
Carole was tempted to say, ‘Bad luck,’ but thought that might be seen as just another example of her lack of gravitas.
‘In this case,’ Nessa Perks condescended, ‘the person we have to look for in our search for the murderer is the woman whose affair with Burton St Clair broke up his first marriage. That woman got a considerable charge out of seeing off his original wife Megan. It was very good for her self-esteem and she reckoned that, following the break-up, Burton St Clair was her property. She has continued to believe that ever since.’
Carole felt she had to intervene. ‘Just a minute, we are talking about fifteen-odd years here.’