Cressida clung to the wisteria vine and set one foot onto the first-floor balcony railing, trying to ignore a spine-cracking drop to the walkway below.

Her chest heaved with exertion. The soldiers who had pursued her across London could only be moments away.

Of all the places she really didn’t want to get caught breaking into, Fife House was top of the list: home of Lord Liverpool, Secretary of State for War and unofficial government spymaster.

Oh, hell. With a swift exhalation, Cressida shifted her other foot onto the balcony and relinquished her grip on the twisted wisteria trunk, only then allowing herself to jump down into the balcony itself, which was dominated by a large, unshuttered window that had been left ajar.

Breathe. Just breathe . For a moment, she crouched amid a drift of bruised wisteria petals with the sulphuric stink of gunpowder still in her hair.

Cressida’s pursuers had been close behind ever since she’d shaken off her guards in the aftermath of a bone-shaking explosion at the Port of London. All were officers. Exactly the sort she did her best to avoid.

Sometimes, in Cressida’s barefoot and often drunken years with first the British army and then the French, she had exchanged information for coinage or rum: perhaps the positioning and morale of troops, whether their supply wagons were stranded on the wrong side of a ravine.

Sometimes, there was a price to pay for that.

Cressida got to her feet: as ever, there was nowhere to go but onwards.

Lady Liverpool was entertaining this evening: the room beyond the balcony blazed with candlelight.

It was quiet, though: good. Her ladyship must have kept her guests corralled downstairs.

Cressida brushed down the green satin skirts of the evening gown she’d stolen before the siege, filched from a French commandant’s wife in an ancient Spanish walled town, where the night was heavy with woodsmoke and the scent of charred herbs.

She tucked a stray ringlet behind her ear, raised the sash window and stepped into the quiet of Lord Liverpool’s library, accompanied by a sudden volley of barking so loud it rent the air.

Cressida caught her breath, making the usual rapid assessment that had saved her life on more than one occasion.

Bookshelves reached all the way up to the embossed ceiling; blazing candlelight picked out gold lettering on leather-bound spines.

Two footmen in powdered wigs and gold-laced blue livery stood by an imposing fireplace of rose-pink marble, imprisoned by a bear.

Cressida stood very still, breathing in the acrid, animal reek of a creature in distress even as the bear whipped around to face her, letting out another volley of excited barking.

It was a dog, of course, the size of a small pony.

Cressida held up one hand, palm outwards. ‘Stop at once. Oh, what nonsense.’

The dog stood easily three feet high at the shoulders and leaped at Cressida with such weight and force that it took some effort to steady herself. Hairy paws landed on her shoulders with staggering force, and Cressida had to gather her strength to remove them, one by one.

‘ Sit. ’

Recognising a true mistress when he heard one, the dog settled back on his haunches, shaking his great ursine head with a spray of saliva.

Cressida turned her attention to the footmen, who had by now scrambled to block her path to the door; these were men trained never to forget a face. They knew, after all, who she was.

‘Lady Liverpool is not at home to visitors.’ The taller footman smirked, even as the sounds of distant merriment drifted into the room from downstairs: wild laughter, a concerto.

His colleague sneered. ‘Out the way you came, milady, unless you’re wishful for us to call the Runners. Scotland Yard is just across the way, after all. That or we can march you out through the servants’ quarters: we always do like a bit of light entertainment below stairs.’

The dog – a Newfoundland crossed with a mastiff, perhaps – let out a low, rumbling growl that Cressida felt through the soles of her feet.

‘Oh, I don’t think we need create a spectacle, do you?

Are you going to open the door or not?’ Cressida asked, gently.

‘ Come .’ This last directive was issued to the Newfoundland cross, now at her side, and together they left Lady Liverpool’s footmen to concoct their excuses for being outmanoeuvred by a fallen woman and a dog.

At the top of the wide marble staircase, Cressida rested one hand briefly on the dog’s vast shoulder as he waited at her side, quivering with anticipation.

‘Come on then,’ she said. ‘I’ll take you to his lordship.’

The Newfoundland whined with longing, the object of all his desires now within reach.

Cressida knew by the time they both reached the foot of the stairs that her command over him had wavered.

A pair of large gilded double doors had been thrown open, and here the babble from within grew ever louder.

Cressida breathed in the scent of over-warm bodies and champagne breath.

There was still time to run away from all this, not that she had anywhere to go, no other choice at all in fact.

Silence descended. With the dog at her side, Cressida walked into Lady Liverpool’s drawing room.

Somewhere, someone dropped a glass of claret-cup, and the bright burst of broken glass rang out.

Cressida caught sight of familiar faces from her youth, people she had known, and some she’d even liked.

Those closest to her turned their backs in a flurry of shivering ostrich feathers and shimmering silk.

It was to be expected. Cressida smiled as the dog left her side, bounding towards one of the side doors, spraying drool and now unstoppable.

Cressida followed in his wake, looking neither right nor left until her companion let out a crescendo of excited barking and surged into the side-chamber, knocking aside an acne-ridden young footman like a single painted ninepin.

Cressida followed her companion into a room with an embossed ceiling and panelled walls hung with portraits of people and horses, all framed in heavy gilt.

She shut the door behind her at speed, which was just as well.

A dark-haired young man of about her own age was vigorously swiving a slight woman bent over a chaise longue.

Her skirts were pushed up around her waist and Cressida just had time to register a head of cropped fair curls and a cry of shocked indignation, which would have been maidenly had it not emerged from the lips of Lady Caroline Lamb.

Someone had drawn long brocade curtains across the tall window that faced out onto Whitehall.

This did little to muffle the tail end of a riot: broken glass and hobnailed boots upon the paving-slabs.

Out in the street, someone was singing one of the new rebel songs, lauding General Ludd in a reedy falsetto.

With one final workmanlike thrust George Gordon, Lord Byron pulled away and turned around to face Cressida.

His fine lawn shirt was in fantastic disarray, both his dark eyebrows raised, his face flushed with spent desire and that wary, irresistible smile upon his lips.

Lady Caroline whirled around, yanking down the fragile skirts of her gown.

Her eyes narrowed as she recognised Cressida. One word was enough.

‘ You! ’

This was too much for Cressida’s companion, who bounded forward to greet his master, both paws upon his shoulders.

‘Show some propriety, Timothy.’ Byron laughed, tucking in his shirt and everything else back into his breeches with his one available hand as he fended off the dog with the other.

‘I thought you said you wouldn’t get another after Boatswain?’ Cressida demanded, as Byron buttoned up the fall of his breeches, one-handed. He ignored Caroline, who was white-faced as she retied her garter, her large, expressive eyes glittering with unshed tears.

‘Oh, Timothy’s not mine,’ Byron said. ‘ Down , you wretched thing. I’m just looking after him.’

Caroline poured herself a brandy from a decanter on the side table and flung herself onto the chaise longue, canny enough not to storm out of the room while she still looked unmistakably like someone in receipt of a flyer.

Byron spread his hands out wide in a gesture of helpless confusion. ‘Dare I even ask what you want, Cress?’

Cressida smiled. ‘I need to get out of the country before they hang me.’ She hated this part: ‘And a loan of a few hundred or so. I won’t trouble you again.’

‘You chose a fine time to come home. It’s a damned thing when the Prime Minister can be shot dead in the House of Commons.

’ For once lost for words, Byron gesticulated at the window.

Outside, rioters howled an approximation of ‘The Cutty Wren’.

Rebel songs meant one thing when all was said and done: a fine crop on the gallows.

‘Whatever happened to that boy who wanted to build the world anew? Revolution is neither tidy nor convenient,’ Cressida said.

Byron frowned at her, then shot a quick glance at his mistress, before switching into effortless French. ‘Darling, I suppose it’d be a fool’s errand to mention Greville at this point?’

Cressida laughed, recalling the mob of siege-crazed British soldiers advancing on her in an ancient Spanish town, forcing her to back up against the bloodstained, crumbling wall where they had shot French survivors.

Step away from the lady. Achingly recognisable, the voice had come from behind them all.

She’d known him immediately, even with the familiar lines and planes of his face darkened with gunpowder, and even in the dusty, bloodied dark green uniform of the Rifles, not dressed for the balls or country houses where in truth he had always been so bored and restless.

She recalled odd details that flew upon her like hornets in a rush of memory and sensation: how Greville hadn’t been wearing his fur-plumed shako helmet and how the dark waves of his hair were crusted with sweat and blood but touched gold by the sun, the dark gaze that had once been full of humour now scorching with slow, deliberate hatred right down the length of her body.

Thanks to Greville, she was still alive.

Thanks to Greville, she had been arrested for treason, brought back to an England on the brink of revolution to face what passed for justice these days, and as of this afternoon was now a fugitive on the run.

‘ Cressida! ’ The panic in Byron’s voice brought her sharply back to the present.

‘I’m going to regret this – listen: the Season’s nearly dead and buried.

I’ve received more invitations to house parties than I know what to do with, but I’ve accepted your cousin’s.

Meet me at Drochcala? It would be wiser to discuss this another time. ’

He wasn’t wrong. A selection of Lady Liverpool’s burlier footmen had advanced into the room; she couldn’t afford to be marched through a drawing room like some kind of criminal.

Instead, she followed Byron’s gaze to the window that gave out right onto Whitehall itself and sketched a mocking curtsey, which he returned with an equally unserious bow. Then she ran.