Greville ran down to the end of the garden, making for the stables.

Oliver, so he’d been told, had abandoned the servants’ table early to check on the horses.

He could only pray that Roberts had the sense to stay put: it would be a kindness to Bute to contain this until he’d been told.

Greville stopped on the cinder path, staring out at the loch-head where grass tumbled down into white sand, all overgrown with drifts of pale pink thrift glowing in what remained of the light: he couldn’t forget Roberts’s spiteful smile, telling him and Cleveland how she’d seen Lady Cressida walking away from the gardens towards the plantation and the hillside beyond.

I thought as it seemed a strange time for a walk, my lord.

Take the money and go , Byron had told her.

Greville battled a futile urge to go after her, alongside an unnerving sense of unreality: how could the loch look so peaceful, and the wide pale sweep of beach away to the west so serene?

This felt like one of the vivid dreams he sometimes had after a battle, but neither brandy nor a lit candle would banish this.

In a household full of civilians who couldn’t be trusted to organise their way out of a burlap sack, someone had to manage a hell’s breakfast of this magnitude.

He recalled the expression of naked nihilism on Cressida’s face, just moments after they’d made love in Chas’s dressing room at Crauford House.

Surely the question wasn’t what Cressida was capable of, but just how little she cared what happened to her?

Greville shook himself like a dog coming out of the loch.

He had to take hold of himself. Somers absorbed servant-hall gossip like a sponge and he knew that Annis had struck Cressida across the face outside the dining room.

Poison was a woman’s weapon, but Cressida had the look of someone who would do the job with their bare hands if she did it at all, in much the same way as he preferred to organise the task himself.

Again, that soldier’s instinct whispered a quiet warning, this time to open the stable door in total silence.

Which meant that Greville was faced with Oliver Tait kissing a tall, sun-bronzed and long-limbed young man clad in salt-stained breeches and a fisherman’s jacket of heavy twill, his honey-gold hair stiff with salt.

Tait had one hand in Jamie’s fair hair and one on his arse.

Oliver saw Greville first. Slowly, Jamie turned around.

Jamie put a hand on Oliver’s arm and then moved to stand in front of him, a lover’s protective gesture. ‘It’ll be quite all right. Greville—’

‘Shut up.’ Greville spoke with such soft savagery that Jamie actually listened, even as Greville recalled with a jolt the way Oliver Tait had looked at him across the bar in the Loch Iffrin Tavern just hours before, for all that it now felt like days.

Tait had recognised him. He and Oliver Tait had never laid eyes on each other before but Oliver clearly knew Jamie, who was Greville’s cousin not only legally by adoption, but also by blood-ties of illegitimacy.

‘Are you an actual Radical, James?’

Jamie shrugged so that Greville really had to restrain the urge to clip him around the ear. ‘Something has to change: surely you can see that? Without a free and fair society, we’re nothing. The poor in this country are treated like animals.’

‘Then I beg you will tell me why the bloody hell you’re up to your neck in a mess that will like as not send most of the Butes’ servants to the gallows for free-trading? They’re not larking about playing at smugglers and getting sent down from Cambridge, are they?’

Jamie flushed then. ‘They were free-trading anyway. I wouldn’t expect you to understand the rest.’

He was the Gentleman, not Rosmoney after all.

It explained those long, otherwise inexplicable absences from Cambridge.

It even doubtless explained why Chas, with his casual resemblance to Jamie, had been shot in London: Jamie could easily have crossed the wrong man, playing this sort of game.

And above all, it explained why Oliver Tait had looked at him, Greville, with such clear recognition in the Loch Iffrin Tavern.

Tait was up to his neck in the Gentleman’s trade in black-market weapons, too: weapons that now waited at the bottom of the loch, although not too far down, almost as easily retrievable as a line of lobster pots.

Greville didn’t wait for an answer, which was just as well because Jamie didn’t look even close to presenting him with one.

It only needed this. Greville measured out each word with ice-cold clarity. ‘Let’s try this again: who in the devil’s name is paying you to ship weapons up this loch and where are they going?’

Jamie gave him a pitying look. ‘Do you really think I know who’s paying me?

The chain of command has to be kept secret, Greville.

Anyway, I don’t keep the money,’ he continued, without a hint of remorse.

‘I’m doing it because it’s the right thing to do: I gave everything to the benevolent fund for the weavers last time.

I just cut through the Pentland Firth and then go down past Fraserburgh and south to Morecambe,’ Jamie went on, as though this were nothing, and not a mission of unhinged danger.

‘There’s a war on. How do you know those weapons aren’t going to end up making their merry way straight across the Bay of Biscay to the French army in Spain, let alone the information that’s probably carried with them?’

Jamie looked momentarily chastened at that.

‘I keep telling him it’s a fool’s errand,’ Oliver cut in, with restrained anger. ‘But he never listens.’

‘No, I would imagine not. Where did you get the boat?’ Greville asked. ‘Did you steal it?’

Jamie gave him a scornful look. ‘Of course not. I take the Wren . No one ever sailed her after my father died. She was just mouldering alongside the quay at Blyth, and she’s pretty tough for a yawl of her size. I’m not doing anything the Norsemen didn’t do.’

‘Of course. And where is she now, if I might ask?’ Greville said, now fighting twin urges to laugh or hit him across the stables. The fucking Norsemen.

‘Only about four miles away, on the quay at Sangobeg,’ Jamie said, impatient. ‘I walked over: word is Fraser MacGuigan’s been patrolling up and down the loch here for days, and if he’s not here, he’s poking about at Loch Eriboll.’

‘I don’t even know what to say. Christ.’ Greville stared at his cousin for a moment, examining Jamie’s face once more for any sign of remorse or regret.

Seeing neither, he resisted another urge to clout him.

‘Next time you want a little excitement in your life, can I suggest you do it in the name of King and country and join the army?’

Jamie smiled at him, but his eyes were hard.

‘Why would I want to serve the King? Thousands of his subjects are starving and yet nothing is done. Why else do you think I’m doing this?

No one of our class cares about injustice and they should: it’s disgusting, the way you all sit around screwing each other’s wives and stuffing your faces like force-fed geese, looking down on everyone else who doesn’t quite meet the standard. ’

‘Shut up,’ Greville said, ferocious. ‘All I’ve got to say about this is at least you’ve given each other something of an alibi. Tait, come with me now. James, I’ll deal with you later but you’d better come into the house. This is a mess.’

‘An alibi?’ Oliver’s voice was toneless with shock, not that Greville blamed him for that.

He didn’t care to judge men for who they chose to bed, not as long as all were willing and none of it concerned his wife.

Greville was no greenhorn, either. He knew quite well that some like Arthur Lascelles preferred other men all their lives, never taking up with women.

But all the same, actually getting caught with another man could see Jamie and Oliver in the stocks, pelted with filth, or even on the gallows: they both needed to be a damn sight more careful.

Not trusting himself to say another word, Greville jerked his head towards the door in an unspoken order.

Following Oliver and Jamie outdoors into an azure-tinted Highland night, Greville’s mind raced as he sorted through twenty years of memory: remarks made by great-aunts and friends of the family when the Nightingale children were brought up to the drawing room.

Some of those comments had been nothing but harmless throwaway observation, others more pointed, even whispered.

Goodness, isn’t Jamie the image of Tristan? (That had always merited a frozen silence.)

Are not Chas and Jamie precisely like peas in a pod, with that pretty fair hair?

Lord, Greville is your image, Sylvia! Crauford always had far more of their father about him, did he not?

Greville scarcely favours his papa at all.

Jamie, on the other hand, was the image of his natural father. Their fathers, natural and legal, had been brothers. Any resemblance between him and Jamie was quite understandable – had Greville actually resembled his own father much at all.

Greville knew quite well that he had never done so.

You have only his hands , Sylvia always used to say, holding out her own for Greville to kiss.

And yet place her alongside him before a mirror and the resemblance was strikingly clear, for all that his mother was a woman and he a man: the long, curved mouth, those tilted eyebrows. Even the single dimple was identical.

Jamie did look exactly how Greville remembered his libertine, fair-haired uncle Tristan, so different a man to his own quiet, thoughtful father. But in that stable, Greville saw for the first time what Oliver had seen in the Loch Iffrin Tavern: as a grown man, Jamie also clearly resembled him.

Greville wondered how much time they had before everyone else saw it, too.