‘Let’s think about this. I suppose with all your involvement with the chaps in Calcutta it’s you we have to blame – excuse me, thank – for this excessively succinct way of communicating the forensic information! The bullet that killed Lionel Conyers (that’s bullet A – we took it out of his body) was fired by a gun they’re labelling “A”. The two bullets that finished off your Russian friend were fired by a different gun – “B”. And the three rifles we took from Flora’s, two service rifles and the third one in the bag, were total innocents and nothing to do with either of the killings. The two service rifles had Troop’s prints all over them as you would expect but the third innocent one had been wiped clean. Now what the hell are we to make of all this?’

‘Easier to start at the end, I think,’ said Joe. ‘Flora, knowing nothing of modern methods of ballistic recognition, was trying to implicate Troop in the murders. I expect she wiped clean the third rifle to make it look more suspicious. And I don’t think we have to look any further than young Claudio to find a reason for her wanting Edgar Troop out of the picture! But then we’re left with the question of the two different rifles used in the two killings. That’s the worrying part… Same modus operandi, even the same cigarette ends left at the scene, but different rifles…’

‘Can’t see what’s so strange about that,’ said Carter. ‘Lots of people in Simla have more than one gun. There are probably more rifles per head of population in Simla than anywhere in the world outside Texas!’

‘True – but,’ persisted Joe, ‘we’re not talking about lots of people in Simla who might shoot for fun or competition or just collect guns. We’re talking about a sniper.’ After years of keeping his head down in the trenches, the word itself still had the power to make Joe shudder. ‘I know their habits. They grow attached to one particular weapon and go on using it. They know its character, its idiosyncrasies – and all rifles have them – and they don’t give it up. I know of snipers, marksmen who went through the whole war using the same weapon. No… “Killing A Gun A, Killing B Gun B” – that’s where the puzzle is!’

He was remembering something that Alice had said about Lionel’s killing that had struck a false note with him but before he could expand on the disturbing thought taking shape the telephone on Carter’s desk gave its customary throaty purr and rattle.

‘Superintendent Carter, here, Simla Police… Ah, yes, indeed I did… You have?… Good man! Seven o’clock this evening? Thank you very much, Patwa Singh. Thank you very much indeed.’

He put the telephone down and turned eagerly to Joe. ‘We’ve got them!’

‘Who’ve we got?’

Carter looked anxiously at his watch. ‘The birds are flying now!’ he said dramatically, enjoying the moment. ‘That was the stationmaster at Kalka. I’d warned him off to tell me if any of our suspects made a booking on a train out of here. I’ve got lookouts covering the roads too. Hang on, Joe!’

He hurried to the door and shouted commands. Buckling on his Sam Browne, he explained: ‘The whole of a first class compartment has been reserved all the way through to Bombay! Two passengers only. And paid for by ICTC. The train goes at seven from Kalka which means that Alice and a companion are probably going to catch the two o’clock local train from Simla to connect with it. In half an hour. Not much time!’

He folded the warrant and slipped it into his pocket. Before Joe could speak again the havildar returned, face bright with excitement. ‘Sahib, sir! Word has come that Memsahib Sharpe passed down the Mall ten minutes ago in a tonga. Two tongas! Their luggage was in the second one! They went west towards the Kalka road.’

‘They? Who was with her?’ asked Carter.

‘The Pathan, sahib. Rheza Khan.’

Dejectedly Joe watched Charlie Carter and his escort swing out of the police compound and set off for the railhead. At the last minute Charlie had turned about and, cupping his hand to his mouth, had shouted, ‘Joe! Change your mind! Come with us!’

Joe shook his head. ‘It’s your affair, Charlie,’ he said. ‘It’s up to you to make the arrest, not me. Don’t forget I’m only a supernumerary. I’ll stay here and mind the shop!’

Joe lingered on the verandah; bitterly he didn’t want to move on to the next thing. He knew very well that care for Charlie’s status in the matter was not truly his motive. Charlie had been right when he’d said he might prove a liability. He was aware that he was deeply reluctant to think of Isobel under restraint. He didn’t want to be there when she was brought to book. He didn’t want to witness the collapse of her long deception, the crumbling of her so carefully constructed position before the world. He went over and over the evidence. Have we got a case? Can we really persuade the world at large, to say nothing of the court, that through all these years ‘Alice’ has played everyone on a string? Sir George? Simla high society? Friends and colleagues in high places? Her closest friend Marie-Jeanne Pitiot? He wasn’t able to share Charlie’s excitement and determination. And now it fell to him to report to Sir George. Joe did not look forward to this.

He stepped into the street to call a rickshaw but was surprised to find himself confronted by Edgar Troop riding into the police compound. To Joe’s further surprise, he appeared to be leading a second horse. He greeted Joe with urgency. ‘Glad to have caught you, Commander,’ he said. ‘Is there anywhere we can talk? Hurry up – we haven’t much time!’

Joe hesitated. ‘Here, I suppose. I don’t think Charlie would mind if we sat on his verandah for a minute or two.’

Troop threw a leg over the horse’s mane and slid to the ground, authoritatively calling out for a syce to take his horse. ‘This’ll do as well as anywhere.’

‘Listen,’ said Troop as they established themselves, ‘I don’t want to force a confidence and God knows this has nothing to do with me but I was just coming back from the chummery and I passed Charlie Carter appropriately accompanied by the full panoply of the law. Six police sowars under Charlie’s havildar, no less! On his way to the station, I believe. Am I right?’

Joe hesitated before replying, saying at last, ‘Well, I don’t know to what extent you’ve put two and two together but since the world will know in an hour or so there’s no reason why I shouldn’t tell you that he was on his way to arrest Alice Sharpe.’

‘And he expected to find her at the station?’

‘Yes indeed. She and Rheza Khan have tickets booked through to Bombay from Kalka. Luggage has been sent in advance and they’ve taken more with them. Fact is – and again, you might as well know – the play is over and Charlie has gone to ring down the last curtain.’

‘I thought that was probably it…’ He leaned forward in his chair, speaking fast and urgently. ‘Now, understand me – I have a great, though reluctant, admiration for Alice, I won’t say affection, but a respect. In the eyes of the good people of Simla and in the eyes of the world at large, I’m something of a scoundrel. You’ll hardly deny that you have thought so. No? Exactly. But I’m as white as the driven snow in comparison with Alice. I expect you hardly know the half of it! The fact is that she’s exploited everybody she’s come into contact with including myself. I’ve performed errands for her – and, by the way, murder has not been amongst them – and I’ve been paid. I am, in a way, a gun for sale but get it into your head that I had no part in the murder of Conyers or that unfortunate Russian fellow.’

Joe cut in. ‘This is all a matter of evidence, Troop,’ he said. ‘We can safely leave it to the police.’

Troop snorted with derision. ‘Alice and Rheza Khan are off to the station with Charlie in hot pursuit but don’t you think it a bit odd that they should have made such a ponderous flit? With the utmost public parade? Straight down the middle of the Mall? And Charlie’s gone down there, handcuffs in his back pocket? Just intercepting the miscreants at the last minute? Does that sound like the Alice we know? Can you imagine that anyone clever enough to fool the entire world for three years would make a move so inept? No! Charlie will proceed to the station to make his arrest and his birds will have flown!’