Jackson flicked the switch on the kettle and made a mug of tea, dividing the little packet of biscuits between himself and the dog. When he had finished, the dog jumped up on to one of the twin beds, circled round and round until it appeared satisfied, and then curled up and fell asleep immediately. It was the bed Jackson would have chosen for himself, being nearest to the door (a room for Jackson was all about exits) but the dog, despite its size, had a remarkably unmovable look about it.

Jackson’s phone vibrated in his pocket like a hefty trapped wasp. Two messages. The first was a text from Marlee asking him if she could have her birthday money early. Her birthday wasn’t for another six months, which seemed to Jackson to give ‘early’ a new meaning. It was a blatantly mercenary message with a perfunctory ‘love you’ added at the end. He thought he would sit on it and make her sweat for a few days. He had never imagined, when his daughter was small and infinitely, eternally lovable, that he would ever develop a combative relationship with her.

The second message was more benign – an email from Hope McMaster. How’s it going? it said. Haven’t heard from you in a while. He tried to work out what time it would be in New Zealand. Were they twelve hours ahead? Early morning there. Hope McMaster was living in tomorrow – a concept that baffled Jackson’s brain. She struck him as the kind of person who might be up early to email. Or was she an insomniac, growing more anxious as Jackson came nearer to the black hole at the beginning of her life? (‘It’s a void,’ she said.)

Jackson sighed and tapped out a message. Am in Leeds. Seeing Linda Pallister tomorrow.

There was an immediate response from Hope McMaster. Fantastic! she replied. Let’s hope she comes up with some answers.

‘Yeah, whatever,’ Jackson said to the phone, sounding to his own ears disconcertingly like his mulish daughter. ‘No,’ he had told her the last time they were together, ‘you cannot have a tattoo, no matter how “pretty”, or a ring in your belly button, a blue streak in your hair, a boyfriend. Especially not a boyfriend.’

Yes, he tapped out to Hope McMaster, let’s hope so.

Hope McMaster’s case had turned out to be a slow-burn affair. For months now Jackson had been reporting back to her, occasional, laconic emails that elicited an immediate chirpy response about the weather in Christchurch (Snow!) or ‘little Aaron’s’ first day at nursery school (I don’t mind telling you I went home and sobbed my heart out). Hope McMaster shared with Julia a (misplaced) faith in exclamation marks. Jauntiness never conveyed itself well in the written word, in Jackson’s opinion.

He had always thought of New Zealanders as a rather gloomy race – the Scots abroad – but Hope seemed as happy-clappy as you could get. Of course, much of Jackson’s information about New Zealanders came from watching The Piano. At the cinema, in the early days of his (true) marriage, before they had a baby, before it all started to go wrong. After Marlee was born they rented videos and fell asleep in front of them. Now, like so much else in Jackson’s world, videos were obsolete.

Nonetheless he was intrigued by New Zealand, although not so much because of Hope McMaster as the fact that last year he had read Captain Cook’s journals and had been impressed by the heroism of his navigation and leadership. First man to sail round the world in both directions. Like the Mallard, a record never to be broken. The Endeavour and the Mallard, consummate examples of the female form.

Cook was a Yorkshireman, naturally. You could but be in awe of the first voyage, the magnificent voyage, to observe the transit of Venus, to find the mythical southern continent, that took him to Tahiti, Australia, New Zealand. Heart of oak. Sometimes Jackson regretted that he would never make his mark on history, that he would never map a new country, that he would never fight in a just war. ‘Be grateful for an ordinary life,’ Julia said, Julia who had always wanted to be extraordinary in some way.

‘I am,’ Jackson said. ‘I really am.’

But.

Imagine sailing into Poverty Bay for the first time, imagine captaining a heroic little three-masted barque to the other side of the world. A new-found land where the sun rises first. Well, Christchurch is really quite English, in many ways, you know, Hope McMaster wrote to him. I wouldn’t want you to be disappointed. You should visit! You would love New Zealand! Would he?

She was two years old when she last saw England. How much could she remember about it? Nothing. How much could she remember about her life before she was adopted? Nothing.

The next planned stop on Jackson’s itinerary after Leeds was Whitby, Cook’s old stamping ground. He rather fancied living by the sea, could see himself in an old fisherman’s cottage built from ancient ship’s timbers. Hearts of oak. He could take a bracing walk along the beach every day in the company of the dog and sink a pint in the evening with old sailors. Jackson, the fisherman’s friend.

Whitby was where Cook had served his apprenticeship and where the Endeavour had started her life as a big-bellied barque, plying the coal trade up and down the east coast. A collier. Jackson groaned at the word. He hated Collier. TV detective. Vince Collier, not a man but a construct, a hybrid of all that was bad, put together by a committee and approved by a focus group.

Mum said I was born Sharon Costello, Hope wrote. Her adoptive parents had been a childless couple from Harrogate – Dr Ian Winfield, a paediatrician at St James’s Infirmary in Leeds and his wife, Kitty, a former model. The Winfields renamed Sharon ‘Hope’.

Now that Mum’s dead – lung cancer, not a great way to go – I feel I can ask these questions about my ‘origins’, Hope McMaster had written. (‘She does like details, doesn’t she?’ Julia said.) It seemed to Jackson that the best time to find answers to Hope McMaster’s questions might have been before her mother died but he didn’t say that.

Hope Winfield married Dave McMaster (runs a successful real-estate office) five years ago and had given up teaching geography at a secondary school to bring up little Aaron and her as yet unborn second child (‘the squid’ – as we call her! ). In the beginning it had been a mere matter of curiosity, she said. She would like to be able to tell the kids more about their genealogy. When you have a child you start to wonder about their genetic inheritance and although my ‘real’ parents will always be Mum and Dad I can’t help but be curious . . . you know how it is, you feel as if you’ve lost something but you just don’t know what it is.

Jackson’s own bad genes had been modified in Marlee (he hoped) by Josie’s more temperate birthright. But what hope was there for Nathan? It wasn’t just Julia’s lungs that were compromised. Her whole family had been riotously dysfunctional in a way that went beyond the Gothic. Betrayed emotionally by her parents, Julia had lost a clutch of sisters, the eldest, Sylvia, to suicide, Amelia to cancer and the baby of the family, Olivia, to murder – by Sylvia. There had been another baby, too, Annabelle, who had lived for only a handful of hours, joined in the grave shortly afterwards by the girls’ mother.

Julia was the only person Jackson knew who could outplay him in the game of personal misery. It was what had drawn them to each other in the beginning, it was what had pulled them apart in the end.

‘One by one all those little birds fell out of the nest,’ Julia said. She claimed there was ‘comfort to be had in metaphors’. Jackson didn’t see it himself. He didn’t point out to her that Amelia had been more like a ponderous bustard and suicidal, murderous Sylvia was worse than a cuckoo.