Hmmm… Somehow, years ago, I managed to love this book, claiming it as a kind of literary adventure, a book that was classily written yet purely about two men on the run, shrugging off any pretence of being 'about' anything except the drama within. This was a time when I rarely kept paperbacks for any potential re-consumption, yet put that one aside. I mentioned it in reviews of utterly different books, as a reference point nobody would actually get. Cut to 2020, and I turned again to it, as Vintage presented a digital copy of a reprint. And something had certainly changed in the intervening decades.

I actually thought this quite cumbersome and lumpen, however much it wants to be highly dramatic. We're, well, we're somewhere with "Goons", and two soldiers flee the march of captive prisoners they're a victim of, knowing all too well they'll have weeks of marching of their own, over the mountains, if they're to escape. They could be British, in some theatre of war in Asia, or perhaps Americans in Vietnam or Korea. One is certainly older and more instinctive than the other, and can speak the "Goon" language. But the book doesn't just put them against the travails of their flight across the titular landscape; no – there is a masterful helicopter gunship pilot pitting his wits against their best at every turn.

So, yes, this is a book that never tries to fudge the issue, and gives us what Graham Greene would have called an "entertainment" as opposed to something more serious. But this time at least I failed to engage. Scenes, struggling as they might to be set-pieces, now seemed overlong, and almost too skippable. The lack of context for the characters didn't help, either. Yes, the final third contains what is definitively a masterclass in nihilism, but this time it wasn't a keeper.

I'll be honest. I was interested in reading this because it was shortlisted for the Booker prize in 1969. You couldn't imagine it being shortlisted today. It's too much of a thriller, too focused on the escape of two male POWs, but it's also tightly written, tense and beautifully paced. The fact that it manages to combine precise description of landscape and a cat and mouse chase between the men and the helicopter following them with a sparseness that recalls contemporary literary novels is remarkable. Occasionally the narrative offers too much detail, for example how is it known that it takes 'an hour and forty-seven minutes' to find their lost suitcase towards the end of the book (and why is that important)? Overall, this races along while forcing you to think all kinds of wider implications. Few of the the Booker winners that have been filmed read like a natural movie. This does and the fact that Joseph Losey filmed it in 1970 is as intriguing as the novel itself. Both are definitely worth checking out.