‘Exactly! The one in Arras argued with his housekeeper about the colour of her dress. And the one in LeMans spent a great deal of time at oculists.’
‘And what do you conclude from all that?’
‘If we assume that Eberhardt was failed because of his eyesight, don’t these four cases strike a chord? The eyes and, in particular, the colour: Aloys’s paintings, Hippolyte’s dress. Didn’t it also play a role in the case of the railway worker from Nancy and also Hector? Can’t we assume that all four were afflicted with....’
‘Colour-blindness?’
‘Exactly.’
‘We need to check.’
‘It’s already been done.’
There was a silence. The professor obviously considered it a valid hypothesis. For my part, I confess I didn’t understand. What connection could that visual defect, which I find a trifle mysterious (and I’m sure I’m not alone in that) have to the man in grey? That was the same question Richard asked.
‘Look,’ replied Bob, ‘out of twelve victims, I can verify four cases. All four are indeed colour-blind. You have to agree that’s an abnormal percentage. It can’t just be a coincidence. There must be a reason, and we can confidently predict the eight others will also turn out to be colour-blind.’
‘I’m sure you’re right, but how does that advance us? You don’t kill a man because he’s colour-blind, all the same. It’s not as if it’s a useful attribute.’
‘I don’t understand either. But first, let’s verify it’s true for the other victims. If so, it will be a step forward, and we will no doubt have an idea, at some point.’
‘I’ll give it some thought. Keep me informed.’
Just at that moment, Jannin came in. We each took an arm and proceeded simultaneously to tell him the story.
‘My goodness, what’s come over you? Have you both got a fever, or have the effects of the yuletide festivities not yet dissipated? Bob, don’t worry about the old woman here (he meant me) and tell me in your own words.’
He listened carefully, obviously intrigued. At the end, he asked a question:
‘What exactly is colour-blindness?’
‘It’s a sight defect, which causes those afflicted to be totally or partially blind to certain colours, particularly red and green. The English physician Dalton suffered from it, and was the first to study it.’
‘That’s what I thought, but , given my limited scientific knowledge, I wanted reassurance before I spoke, to avoid saying anything stupid. Even so, surely you’re not trying to make me believe that your story about colour-blindness has anything to do with these murders? It doesn’t make any sense. If you can convince me it is, you’re much smarter than I thought.’
‘One thing is certain: it’s a relatively rare affliction. There aren’t any statistics, but let’s suppose for the sake of argument that twelve men in a hundred are affected (women aren’t, because—like haemophilia—it’s tied to the X chromosome) . That would be a maximum. It would mean that each victim had a one-in-eight chance. We already have four, which means that that in itself is a chance of one-eighth to the power four, in other words, one in four thousand and ninety-two. So you can see that the probability of all twelve being afflicted would be astronomical. In reality, it’s impossible that it’s due to chance. We’ve been looking for a common link between the victims for weeks. I’ve just found one. I have a right to be taken seriously.’
‘Very well. I have no option but to follow your lead. What are your instructions?’
‘For each of the eight other victims, check that my assumption is correct. For the two in the Paris region, that should be easy: Chauvin’s best friend is a shopkeeper in Rue du Sentier. As for Mellot, his circle of friends frequent Les Halles. For the other provincials....
‘I’ll call the Police Judiciaire right away.’
After issuing the instruction, we went to interview the friends of the victims of Villemomble and Melun and, to our surprise, because the affliction frequently went unnoticed, obtained the hoped-for confirmation. That meant six out of six.
From Les Halles to Le Quai des Orfèvres is not far. Some of the information was already there waiting for us, and within the next half-hour, we had all the replies. Everything was confirmed: twelve out of twelve.
As we were about to get back into the car, Bob asked Jannin a question:
‘Look here, Jannin, if you needed twelve colour-blind people, how would you go about it?’
‘It would be quite difficult. You can’t tell by looking at someone, and it’s not registered with the town hall. I would have thought that the simplest method would be to place an ad in the personal columns.’
At these words, Bob jumped out of the car and went back into the building. He emerged a few minutes later and announced:
‘Chauvin subscribed to Lutèce. We’ll drop by.’
Twenty minutes later, we were leafing through the issues for April and May. It was I who had the honour of finding it. In the issue of May 2, on the second page, was thefollowing advertisement:
Seeking COLOUR-BLIND individuals for a perfectly legitimate confidential mission, incurring no risk.
Maximum duration: 24 hours
ONE THOUSAND FRANCS reward, plus travel expenses.
STRICTLY CONFIDENTIAL. ABSOLUTE DISCRETION REQUIRED.
Write, giving details and curriculum vitae, to Paul Bernard, c/o P.O.Box 118, Paris.
The advertisement had been sent by post, together with a money order. The address given: 84, Ave. des Champs-Elysées, was false (there is no 84, the numbers go from 82 straight to 88). The advertisement had appeared in the principal Paris newspapers and the principal regional ones. At P.O.Box 118, seven months after the advertisement was placed, there was no information available.
Richard, whom we went to see to ask for his advice, was now completely on board. He agreed with Bob that the newspapers should give the matter full publicity.
Jacques Vital had come to
