Vast peaks the colour of ash burst up out of the dark, swirling water of the fiord, while veils of mist cling like toddlers to their jagged sides. Waterfalls tumble down from the clifftops, each one tossing its load into the deep basin below with a powerful yet light-hearted abandon that both thrills and astounds me. The sky above is a faultless Tiffany blue, blemished only by the merest suggestion of cloud, and I lift up my chin to gaze at it, overwhelmed yet again at its colossal breadth. It’s as though my senses are lined up one by one, like soldiers on parade, each one ready for action. I can see and hear the awesome beauty of this place – but I can feel it, too, just as I can taste the spray in the air and feel the wind rushing through my hair. It is impossible not to be moved by Milford’s might and magnitude, inconceivable not to feel privileged simply to be here.

I tear my eyes away from the view in order to steal a glance at Tui. Like me, my half-sister has been wowed into stillness, the frothiness of her irresistible personality temporarily subdued by wonder. Beyond Tui and also with his eyes trained on the water, Kit looks utterly lost in thought. But as if he can feel the weight of my scrutiny, he looks round and catches me staring at him, the sides of his mouth dancing upwards in an easy smile before I have time to turn away.

Around Billy, I often feel as if I am the one driving the conversation forwards, and that to a certain extent, at least, he reacts to my remarks, rather than vice versa. Our friendship trots along with the ease that comes only once you have spent years in another person’s company, and are therefore privy to all their foibles. With Kit, however, the opposite is true, because although he is easy-going and approachable, I still can’t read his expressions, or those little tics that so often give people away. When he fixes me with a look like the one he is giving me now, so genuine in appearance yet so disarmingly kind, it makes me feel strangely bashful and unsure of how to react.

Further embarrassment is avoided thanks to a sudden collective shriek. The ferry driver has aimed the bow of the boat right under the largest waterfall, soaking two thirds of the top deck in the process.

‘Tui!’ It’s Griff, calling across from the opposite railings.

‘Come and see what I’ve found,’ he says, beckoning with a hand, but Tui is already slipping and sliding her way across the wet boards towards him.

‘Watch out!’ I shout, just as Kit yells, ‘Bloody hell!’ and the two of us leap forwards and catch one of Tui’s arms each at exactly the same time, saving her from an almost certain collision with the floor.