The other man said nothing, but stared at Quinn with a distracted hostility.

‘I am looking for Grant-Sissons. I am Detective Inspector Quinn of the Special Crimes Department.’

‘I am Grant-Sissons.’

‘I was looking for an older man.’

‘You want my father.’

‘Is he here?’

‘Yes. But he’s resting.’

‘It’s very important.’

‘Who did you say it was?’

‘Quinn. Inspector Quinn. He will be expecting me, I’m sure.’

The door was shut in Quinn’s face.

An enquiry came from Macadam’s end of the passage. ‘Is everything all right, sir?’

‘He’s here,’ said Quinn.

The door began to open once more.

The workshop was lit by an oil lamp that hung from a hook in the ceiling. It cast a feeble yellow wash over what appeared to be a cave hollowed out inside a mountain of scrap metal and general refuse. Grant-Sissons lay on a camp bed, a coarse, grubby blanket pulled up to his chin, his hands hidden from view beneath it. His bed was like a raft floating on a sea filled with the least buoyant flotsam and jetsam imaginable: rusting cogs, the skeletons of obscure machines, industrial coils of copper wire and other electronic components, a detritus of useless parts and tools. The inventor’s face had a sickly tinge to it that Quinn had not noticed before. He felt instinctively that he was in the presence of a dying man. Perhaps now at last that unusually persistent bitterness made sense.

With every step, Quinn’s foot either came up against a new obstacle or came down on something that crunched or scraped or buckled under his weight.

‘So.’ Grant-Sissons’s voice was weak and worn-out. ‘You have come to find out the truth about your father.’

‘I am more concerned, at this present moment, with a current investigation.’

‘If this is about that girl, I’ve told you, Waechter is behind it …’

‘It is likely that that attack was a hoax. However, another woman has been attacked and killed, and unless you know of a way to bring corpses back to life, I fear that this will not prove to be a hoax.’

‘Why do you want to talk to me about this? I know nothing about it.’

‘The victim was a film actress of sorts. She had been employed by Visionary Productions. You were seen in Leicester Square outside the theatre which was presenting a film in which she appeared. You were seen to behave in a manner that may be described as erratic and aggressive, as well as suspicious. The next time I saw you, you were outside the Middlesex Hospital where you had gone to make enquiries about the girl who had apparently been attacked. The incident had obviously made some impression on you. Perhaps it had inspired you to carry out your own attack, only you went further.’

‘I told you, I was at the hospital on my own account. As you can see, I am not a well man.’

‘Today a bomb was placed outside the office of the Daily Clarion. We are currently pursuing the theory that both the murder of the actress, Dolores Novak, and the bomb outrage were motivated by a desire to damage the interests of the film industry. The proprietor of the Clarion is an investor in Visionary Productions. He also publishes a weekly organ promoting film production and exhibition. The home-made bomb was placed inside a film canister. This seems consistent with our theory, as an embittered perpetrator with a grudge against film people might consider it ironic to use one of the tools of their trade against them. Do you not think?’

‘It’s an interesting theory.’

‘It would require someone with a certain degree of technical and scientific proficiency to construct, prime and detonate an explosive device, do you not agree?’

‘And you think that I am this person? But that is a conclusion of startling ineptitude and stupidity, Inspector. It is a travesty of logical deduction. Do you think I am the only man capable of constructing such a device?’

‘Ah, but you are the only one who also has a viable motive, so far as I am aware.’

‘And there the whole absurdity of your position is revealed, in that “so far as I am aware”. Surely even you must be able to grasp the possibility that your perpetrator may simply be someone who is not yet known to you? Inspector Quinn, after I saw you outside the hospital, I came here and took to my bed. I have not stirred from it since, except to discharge the necessary functions of my body. My son has been here with me the whole time, tending to my needs.’

‘Your son could well have placed the device on your behalf.’

‘But he has been here the whole time, I tell you. By all means, ask him.’

‘It’s true, my father hasn’t moved from his bed the whole time. And I haven’t set foot outside this … place.’

From a legal standpoint, a father and son each providing the alibi for the other rather left something to be desired. However, there was something about the bitter, resentful despair in the son’s voice that inclined Quinn to believe he was telling the truth. ‘Someone else may have put it there for you.’

‘I’m dying, Inspector Quinn. I have no wish to hurt anyone. My only remaining desire is for my part in the development of the motion picture camera to be acknowledged, and for my son to receive the financial rewards that should have been mine. The only weapons I have ever used in my fight are peaceful ones. I have stood up and spoken out. I have picketed. I have written letters. I have canvassed support. But always, I have been ignored. I am resigned now. I have no energy left to continue the fight. And I am not sure that Malcolm has the will to carry it on after my death. It will all have been for nothing.’

‘What’s wrong with you?’

‘I have cancer.’

Quinn remembered the bandage he had seen on Grant-Sissons’s hand. ‘In your hand?’

‘It started there, but it has spread. I was fortunate. I had some weeks of remission. I tried to use that time to make one last protest. And to see you, of course. But the disease is racing through me now. I have seen the end. The horrible end. There is no way to stop it. Do you really think a man in my position would run around planting bombs?’

‘Why did you want to see me?’

‘I have already told you, I knew your father.’

‘How well did you know him?’

‘We worked together as business associates. He came to me with an idea for an invention. He hoped to combine the techniques of photography with the properties of X-rays, thereby developing a machine that could capture images of the internal arrangements of the human body, which he believed could be used to facilitate diagnostic practice in medicine.’

‘What happened?’

‘We were forced to abandon our work.’

‘Why?’

‘My research assistant became ill. She – my assistant was a young woman – Louisa … Louisa Grant-Sissons. She was my wife. Louisa volunteered to be the subject. She was captivated by the magic of it. By the idea of having the inside of her hand made manifest. Of seeing the delicate interconnections of countless little bones. We took many hundreds – thousands even – of photographs of her right hand, exposing her to radiation over and over again. We now know the harmful effects of such rays, but at the time, no one … no one anywhere knew. We were not the only ignorant fools. Of course, I should never have permitted it. I should have insisted that I was used as the subject. But she was so charmed by the wonder of what we were doing, she begged us to conduct our experiments on her. And we were swayed, both I and your father, for we were both in love with her, you see, and neither of us had it in us to deny her what she wanted. She developed the cancer in the bones and tissues of her right hand, precisely as I have. Only in her case it took hold immediately. Whereas it has lain in wait for me, biding its time over the decades, waiting to find me at my weakest and most disappointed.’ Grant-Sissons fell silent.