The Luminaries is a book to lose yourself in for days, weeks or months. If you haven’t yet succumbed to the hype about this huge saga, don’t resist. Switch off your smartphone, laptop, etc, and get stuck in.

The size of two bricks, it sat by my bedside for a while as I dipped into slimmer, easier-looking things.

When I heard the author, Eleanor Catton, was to be a star turn at the Oxford Literary Festival in March, I hauled it on a train to the Lake District — and almost forgot to get off at Penrith.

It’s a bodice-ripping, opium-fuelled story, told in the form of a mystery, with elaborate astrological diagrams which I failed to understand. I loved every word, and only managed to put it down each day because I knew I would miss it when I finished.

Set in the New Zealand gold rush, it features a newly-arrived young immigrant, Edinburgh lawyer Walter Moody, recovering from something horrific, but at first unrevealed, that happened during his stormy voyage.

He enters a hotel room where 12 men — a chaplain, a Maori gemstone hunter, a banker, a newspaperman, a hotelier, a goldfields magnate, a Chinese goldsmith, a commission merchant, a chemist, a shipping agent, a justice’s clerk, and an opium-smoking hatter — are holding a secret discussion. Moody is spellbound and so are we.

There are also two women — the mysterious Lydia Wells, who arrives to claim the pile of gold left in a hermit’s cottage (is she really his widow?), and Anna, a whore with a heart of gold who has won the heart of most of the men in this tiny settlement.

Catton’s storytelling is in some ways straightforward, with an all-knowing narrative voice, old-fashioned rundowns of each character and a cliff-hanger at the end of nearly every chapter.

There is plenty going on below the surface. On Moody’s arrival he looks for constellations to guide himself, but everything is topsy-turvy. “He found Orion – upended, his quiver beneath him, his sword hanging upward from his belt; Canis Major – hanging like a dead dog from a butcher’s hook.”

I couldn’t bear the idea of saying goodbye to the characters (the enigmatic Moody, Lydia, Anna and the brilliantly named Emery Staines).

There is eavesdropping and assignation, conspiracies and secrets. There is even a seance, not out of place in a 19th-century pastiche, but perhaps a metaphor for how we are never quite sure who is alive and kicking, and who is the ghost knocking on the coffin.

Most of the novel’s 21st-century cleverness was probably lost on me, but I did absorb the idea that “one should never take another man’s truth for one’s own”, as Moody says.

For me, this enormous book was a delight from start to finish, with every one of its 832 pages helping to illuminate our path through the mystery.