‘Before you start dressing to impress the widow, Joe, why don’t you get acquainted with my razor?’ George’s jovial voice was brisk. Not in the least sleepy. ‘No newfangled patent safety razor on offer, I’m afraid. I always use an old-fashioned cut-throat. You must pardon the expression in the circumstances.’

Bonnefoye shrugged and grinned and went with the smooth efficiency of a valet to select a shirt.

‘Let me mark your card, Joe.’ This was the old Sir George, good-humouredly in charge, presiding. ‘Now, the present Ambassador is the Marquess of Crewe. Can’t help you there. Never met the chap. Though I was well acquainted with his predecessor. Hardinge. Viceroy of India for many years. And a good one. Anyway, play it by ear and if it seems appropriate to do so, convey my respects and good wishes to whoever seems to be expecting them . . . you know the routine, Joe.’

‘I don’t suppose the top brass will be parading for a mere Scotland Yard detective and a widow on a lugubrious mission, sir.’

George pursed his lips for a moment, assessing the social niceties of the situation. ‘You’re probably right, my boy. Six o’clock. Dashed inconvenient time for them to be landed with handing a distraught old lady over to the bluebottles. They’ll be preparing to welcome guests for whatever shindig they’ve got planned for tonight. Sociable lot at the Embassy! Always some sort of soirée on. You’ll probably find they’ve tethered the old girl to a gatepost outside, awaiting collection.

‘No, Bonnefoye! Not that one! Wherever did you get your training? He’s not bound for the golf course! Find a boiled shirt, my dear chap! Yes, that’ll do. Collars top left. Grey felt hat in the cupboard. Nothing grander. Don’t want to look as though you’ve turned up for the canapés.’

At five minutes to six Joe stood, getting his breath back, in front of the Embassy, transfixed by the perfection of the Louis XV façade. Balanced and harmonious and, in this most grandiose quarter of Paris, managing to avoid pomposity, it smiled a welcome. He almost looked for George’s gatepost but of course there was none. An elegant pillared portico announced the entrance; doors wide open gave glimpses of figures dimly perceived and moving swiftly about in the interior. As he watched, electric lights flicked on in all the windows of the first two floors. The reception rooms. Obviously a soirée about to take place.

He collected his thoughts and strode to the door.

The liveried doorman barely glanced at the card in his extended hand. ‘You are expected, Commander. Will you follow me?’

He passed Joe on, into the care of an aide in evening dress who came hurrying into the vestibule to shake his hand. ‘Sandilands? How do you do? So glad you could come. Harry Quantock. Deputy assistant to the Ambassador. You’ll have to make do with me, I’m afraid, sir. His Excellency sends his greetings – he’s at the moment rather tied up with the string band.’ At the upwards flick of an elegant hand, Joe caught the sounds of a small orchestra essaying a piece of Elgar somewhere above their heads. The deputy assistant grimaced. ‘French band, English tunes . . . not a good mix. I sometimes think they do it on purpose.’

‘Still seeking revenge for Waterloo?’ suggested Joe. ‘Ouch! I’d surrender at once.’

‘We won’t hear them in the red salon, come with me.’ Quantock led him across the impressive space in front of them. Airy, well proportioned and sparely decorated. ‘Le hall d’entrée,’ announced his guide with a perfect accent.

Joe had an impression of cool grey and white marble tiles leading the eye to the graceful curve of a great staircase. The delicate wrought-iron handrail outlining it sparkled with gold and bronze, promising further wonders as it wound upwards.

Quantock leaned to him and confided: ‘Most of the refurbishment was done with impeccable taste by Napoleon’s favourite sister. And there she is – Pauline Borghese.’

Joe nodded in acknowledgement as they passed her portrait. The young princess, slim and lovely in her high-bosomed gown, was as handsome as her house.

‘Pity about the curtains, don’t you think? Red velvet!’ Quantock was shuddering. ‘Too Edwardian for words! And the theme continues through here in le salon rouge.’ He paused by a closed door. ‘Your charge, Lady Somerton, is in here, taking sherry and flirting with the Duke of Wellington. They will do it! His Grace still exerts a certain power over the ladies.’

Joe entered a room richly decorated, in contrast with the restrained hall. In the centre, a gleaming round mahogany table stood precisely in the rosette of a deep red turkey carpet and was overhung by a stunning chandelier. Gilded mirrors applied to each of the red walls reflected the flickering lights of candles in sconces, and in the middle of all this magnificence Joe had to hunt for the figure of Lady Somerton. She was standing at the end of the room, empty sherry glass in hand, still, black-clad, almost a shadow. She was looking up at a portrait. Transfixed, she did not hear them enter.

As they drew near she began to speak: ‘Arthur Wellesley. The Iron Duke. Now there was a man one can admire! So handsome! So competent! I’m just surprised, after what he did to the French, that they allow us to display him, Mr Quantock.’

‘His Grace was himself Ambassador for a year here in 1814, immediately before his victory at Waterloo, your ladyship,’ Quantock reminded her. ‘And therefore takes his rightful place on these walls.’ He performed the introductions. ‘May I refill your glass? And how about you, sir? Would you like some sherry?’ He went to pour the drinks himself from a sideboard, tactfully leaving Joe to continue the conversation.

‘His quality leaps from the canvas, don’t you agree?’ she continued, determined apparently to hear his views.

‘It’s all in the nose, I believe,’ said Joe, annoyed that the widow appeared far more interested in Wellington than in himself.

‘I beg your pardon? The nose, did you say?’

‘Yes. Look at it. An ice-breaker! Apromontory! Your hero could have fought a duel with Cyrano and they would have needed no other weapons.’

At last she smiled. ‘Noses. In the Bois. At dawn. I’d have put my money on the Duke.’

Her attention caught, Joe moved easily into the routine of expressing sorrow for the death of the lady’s husband. His smooth sentiments were graciously received, helped along with sighs and sips of sherry. Quantock politely sought the most recent information on the tragedy and Joe gave him an acceptable and highly edited account. The task before him was to point this uncertain dark horse at a rather taxing fence and he wanted to avoid scaring her off. Without appearing to do so, he studied the widow, assessing her strengths and qualities. Exactly what he was expecting. Apart from her age. She was middle-aged, possibly as much as forty, but at any rate, more than a decade younger than her late husband. Quite a normal age gap in military families. He could imagine that, with promotion in mind – possibly Colonel the next step – Somerton had been taken on one side by a superior officer and advised to marry. And, one summer, on home leave, he’d met and courted this woman. What had she said her name was? She’d rather particularly during the introductions corrected young Quantock. ‘Lady Somerton no longer,’ she’d informed them. ‘With Sir Stanley dead and the title gone to his son, my daughter-in-law is the present Lady Somerton. I am now to be addressed as Catherine, Lady Somerton.’ The voice was educated, Home Counties.

Her face was pale, enlivened by a gallant touch of rouge along the cheekbones. Quenched but pretty. Her hair was light brown, not greying yet, her eyes hazel. She’d chosen her dress well. Black, of course, but silk and well cut. The drama was relieved by a double strand of pearls around her throat and matching pearl earrings that peeped out just below her bobbed hair.