Kai’s mouth twitched and he began to smile, finally relaxing. ‘You have a point there. I hadn’t thought of it that way.’

‘Not that I want to have someone trying to kill me,’ Irene hastily added. ‘But, you know, given the choice . . .’

The cab rolled to a stop and the driver called down from his perch, ‘We’re here, madam, sir. Will you be wanting me to wait?’

‘No, thank you,’ Kai said. He paid off the driver while Irene clambered out of the cab, already regretting her return to long skirts. One really didn’t appreciate trousers until one wasn’t wearing them any more.

The two of them looked up at Vale’s windows, as the cab rattled off into the fog, its ether-lamps glaring eyes that vanished into the darkness. A dim light showed round the edges of Vale’s curtains.

‘At least he’s in,’ Irene said. From time to time she regretted this world’s lack of convenient mass communication. ‘It’d be annoying if he’d been out on a case.’

Nobody answered Kai’s knock, but Irene didn’t have to use the Language to coax the door open. Kai already had a key. He led the way up the stairs. Irene followed. She reassured her slight flickerings of nervousness – why didn’t anyone answer? was anything wrong? – by reminding herself that it was coming on to eight o’clock at night. Vale’s housekeeper might well be out. Vale himself would recognize their footsteps, and he might in any case be several miles deep in experiments or research.

‘Vale—’ Kai began, opening the door at the head of the stairs. Then he stopped in his tracks.

‘What?’ Irene demanded, ducking under Kai’s arm to see what was going on.

Vale’s rooms were in as much of a state of controlled clutter as usual. His scrapbooks and files were organized neatly, scrupulously tidy and alphabetical, but other than that, the place was full of stuff. Laboratory equipment was strewn over the main table, with several crumb-dusted plates perched beside the test-tubes. Boxes filled the corners of the room, piled on top of each other in a desperate attempt to use all the limited space available. Various relics from past or current cases lay along the mantelpiece, or fought for space on the bookshelves. The ether-lamps were turned to half-strength, leaving the room in dimly flickering light, and the fire had burned down to embers. Newspapers littered the chairs and floor, as if they had been frantically rifled through and discarded page by page.

Vale himself lay on the sofa. He was a tall man – but, sprawled as he was, he’d lost all his usual grace and was a lanky tangle of limbs. One arm was half-thrown across his face. He was only semi-dressed, in a dressing gown over shirt and trousers, and clearly had not been planning to go out.

He didn’t react to their words. He didn’t even move.

It was astonishing how pure nightmare could quite literally put ice in one’s veins. An attack on us, now an attack on Vale, too . . . She and Kai were both moving across the room in the same moment, without even having to say anything. The only reason Kai reached Vale first was that he’d entered the room first.

Kai grabbed for Vale’s wrist, fingers clasping it tightly, then sighed in relief. ‘There’s a pulse,’ he reported. ‘But it’s slow.’

The wave of relief that hit Irene was so strong she could taste it. ‘Thank god,’ she said. ‘But why . . .’

An answer came to mind. It wasn’t a pretty one. She took Vale’s wrist from Kai and peeled back his sleeve, checking his forearm. She wasn’t entirely surprised by what she found. It did, after all, go with the territory of being London’s greatest detective, in a world where stories could come true and life too often followed narrative. ‘Look,’ she said, pointing to the needle marks.

Kai bit back an oath. ‘But he said—’ he began, then stopped short.

‘What did he say?’ Irene asked softly. She checked Vale’s pulse herself. It was slow but steady.

Kai turned and walked across to turn up the lights. ‘He said that he didn’t use it any more.’ He didn’t look at Irene.

‘When did he say that?’

‘A few months ago. It wasn’t long after we met, the three of us. I, you see . . .’ Kai was nearly stuttering in his attempts to find an explanation. She hadn’t heard that speech pattern in him before. ‘I found the syringe and the drug—’

‘Which drug?’

‘Morphine.’ Kai turned back to her. ‘Irene, I swear, he said he’d only used it occasionally, and not at all now that his practice had become more interesting. I don’t know why he’d be taking it now.’ His face showed something of the panic of a child who’d found out that a fundamental pillar of his world was no longer solid. ‘Could someone else have forced it on him?’

It was certainly possible. It just wasn’t very likely. ‘I suppose we won’t know until we can ask him.’ Irene laid Vale’s arm back across his body, and brushed his dark hair back from his face. His skin was hot under her fingers. So human. So fragile. And if someone was trying to kill her, then was he a target, too?

She had to find a way to protect them – all of them. And she had to talk to her superiors, urgently. The time for professional detachment was over.

It would have been a perfect trap, the cold unpleasant voice at the back of her mind pointed out. Incapacitate Vale, arrange a bomb or something similar, and expect Irene and Kai to run into the danger zone the moment they saw him lying there. It was a very good thing that the attempted murderer or murderers, whoever they were, didn’t have Irene’s own imagination.