The inspector smiled uncertainly at Westhorpe and seemed relieved when Joe sent her back into the bedroom and led him through to the scene of the murder.

‘Notebook, Cottingham?’

‘Got everything you might need in here, sir,’ said Ralph. ‘When I heard you were working the case I thought I’d better bring along the old “Murder Bag”. Always keep it ready. Some of the top blokes don’t bother but, like you, I’m a keen disciple of Sir Bernard.’

Joe nodded his approval. He knew the bag would contain everything he needed: fingerprint kit, evidence bags, tweezers.

‘Got your rubber gloves, Cottingham?’

‘Sir! Julia doesn’t let me leave home without them. Never know what you’re going to fish out of the Thames or the sewer!’ He looked around him at the ravished grandeur. ‘Nasty. But it beats working in an alley behind the Ten Bells which is where I was last week. Sketch of the crime scene first, sir, before I glove up?’

Joe had worked on one or two cases with Cottingham and knew him to be both clever and diligent. Nothing escaped his sharp brown eye and he had a neat drawing hand combined with an accurate sense of proportion. ‘Start with the body, will you, Ralph? The pathologist should be here at any moment and it will be good to give him a clear run.’

‘Sir!’ said Cottingham, already filling in the boundaries of the room on a sheet of squared paper.

‘Oh, and you’ll have observed the pieces of broken glass from the window . . . Plot as many as seems possible, will you? Size of shards and position. A pattern may emerge. As with the blood spatter. Get that down too.’

‘Someone I ought to know, sir?’ said Cottingham without a break in his sketching.

‘Sorry. This was Dame Beatrice Jagow-Joliffe. She was attending a party below, returned to her room just after midnight and was discovered, as you observe, about half an hour later by Constable Westhorpe.’

Cottingham paused in his work and looked up questioningly at Joe. ‘Looks like a burglary that went wrong. Is that what we’re thinking, sir? She disturbed a burglar. Anything missing?’

On cue, Westhorpe emerged from the bedroom, a red leather jewel case in her hand. She opened it and diamonds flashed from the black velvet interior. ‘This was under the mattress, sir. A diamond necklace. Under the mattress! The second place any thief would look! Why on earth can’t people use the hotel safe? He didn’t stay long enough to search properly. Just snatched the emeralds and ran.’

‘The emeralds?’ both men said in unison.

Westhorpe walked over to the corpse. ‘At the party she was wearing the Joliffe emeralds. Family do – of course she would be wearing them. Not round her neck any more and not in her room. And look, sir . . .’ Peering closely, she pointed with a finger. ‘An abrasion, bruise, cut, something there. Someone’s pulled at the necklace. Roughly, you’d say, and made off again back the way he came through the window. It was a burglary, evidently!’

‘Thank you for your observations, Westhorpe. Note it down. Have you checked the bathroom?’

With a lingering glance back over her shoulder at the crime scene, Tilly returned to her duties and they heard the banging of cupboard doors as she resumed her steady routine search.

Released after a suitable interval by the vigilant Armitage below, Joe guessed, the next to arrive was the pathologist and, again, this was a man Joe had worked with before, perhaps the best the Home Office could supply. Joe began to see a pattern of selection at work. The top brass had obviously been busy on the telephone for the last hour in an effort to assemble this particular grouping of talent, and the gravity and delicacy of the task ahead were being alarmingly underlined. There was more riding on the quick solution to this mystery than the sensibilities of the Ritz hotel, he realized.

‘Good to see you again, Dr Parry!’ Joe greeted the portly man who bustled in, wheezing from his ascent of four flights of stairs.

‘And you, Commander! Buggers wouldn’t let me use the lift! Your orders? Curse you then! Now, what have you got to show me that’s so urgent it couldn’t wait until dawn?’

Joe led him to the body. ‘Died just after midnight. A police witness before and after you might say. The victim was under observation by my sergeant the whole evening and I expect he can tell you what she ate, how many glasses of champagne she drank, who she talked to . . . everything but how she died.’

‘Well, that’s obvious,’ said the pathologist. ‘Hardly need to open my bag but I’ll go through the motions. Better get this one right, I think!’ He knelt and studied the body. ‘All observations are subject to further elaboration and adjustment following a complete PM, you understand, but I’ll give you my first impressions if that’s a help.’

Joe nodded.

‘I’ll just take the temperature to confirm time of death,’ he warned.

Joe and Cottingham discreetly looked the other way while he did this.

‘She’s been murdered. By a series of blows about the head delivered with some force or passion – five or six – by a blunt instrument. We’ll probably discover her skull’s smashed. The profile of one of the wounds – look, this one here across the left cheek – is so clear you can tell it was a long thin implement. Can anyone see a bloodstained poker about the place by any chance?’

‘Fire dogs in the hearth, sir,’ said the inspector. ‘Thrown about but there’s shovel, brush and tongs present. No poker. None observable so unless it’s wedged under the corpse it left with the killer.’

‘Not under the body,’ said the doctor, easing it over.

Joe glanced at the window. ‘How very odd,’ he said.

The pathologist checked his thermometer. ‘Almost two degrees temperature loss so that confirms what you’re telling me.’ He turned his attention from the body to the bloodstains spattering the walls, carpet and furniture. ‘You know, judging by the intensity of the flow, I’d say that the first and most violent blow was struck right here on the rug in front of the fireplace. Someone lost his temper, helped himself to the poker and hit her. Scalp bleeds freely, you know. I’m looking at that spurt of gore there . . . reaches as far as that chair. Turn it back on to its feet and you’ll see what I mean.’

‘Got it, sir,’ said Cottingham quietly.

‘Even odder,’ said Joe.

Parry pointed to further bloodstains. ‘Then she reeled away . . . fought him off . . . and did a sort of danse macabre around the room until the coup de grâce was delivered and she collapsed where we see her now. It could have been noisy, Sandilands. Someone might have heard her screaming. There’s bruising on her hands and lower arms where she’s fended off the blows so she must have remained conscious for a while.’

‘Her clothing appears to be disarranged, Parry,’ said Joe. ‘Any views at this stage?’

‘Shan’t be able to tell you if she’s been subjected to an attack of a sexual nature until I’ve examined the body at the hospital but . . . oh, I don’t know . . . time of the essence and all that . . .’ Joe went to inspect Cottingham’s drawing while the pathologist probed more deeply into their problem. ‘This is a bit queer,’ Parry said finally. ‘It looks as though she’s been interfered with. . . dress torn, breasts – you’d almost say on display, wouldn’t you? – but down below everything appears to be shipshape and Bristol fashion. She’s got on one of those all-in-ones . . . what do they call ’ems?’

‘Camiknickers,’ supplied Westhorpe from the doorway.

‘Thank you, miss,’ said Parry, looking from Joe to Westhorpe in astonishment.

‘It’s Constable, sir,’ said Westhorpe and she retreated back into the bathroom.

‘Indeed! Yes, well, these garments are all in one piece and button up the front. Camiknickers, as the young lady says. Make a girl practically impregnable,’ he smiled, ‘and I use the word advisedly. And all the buttons are done up. But, as I say, I’ll have more for you later.’