I first read Kolymsky Heights during a heatwave a few years ago in Ukraine. Lying sweltering in an unbearably stuffy hotel room in Kiev, I'd never felt colder, immersed in the bone-chilling world of hero Johnny Porter, huddled in the depths of the Siberian winter.

Kolymsky Heights is, on first analysis, just another spy thriller. First published in 1994, it is essentially a late cold war era man-on-a-mission thriller – with the emphasis firmly on the word cold. Porter is the only westerner who can hope to break into and out of a top secret scientific research base that is literally hidden inside a mountain in Siberia. (So secret is this base that nobody who ever enters is allowed to leave alive.)

Porter, however, is descended from Canadian Inuits, who remain – physically, ethnically and culturally – virtually identical to their Siberian counterparts, despite the decades-long political rift between the two. That, alongside his linguistic skills – he also has to pass himself off as a Korean at one point – makes him the only spy able to get anywhere near the base without arousing suspicion.

I've never read a thriller that so successfully transported me to a hitherto unimagined place. After a few racy globe-trotting chapters in which Porter is painstakingly inserted into his undercover role, we enter the dark, icy world of the Siberian winter. And it never gives up its grip until the end.

The plot, viewed dispassionately, is ridiculous. The chain of events that Porter needs to get right in order to engineer his audacious act of espionage is long and fragile. But Davidson has a such a disarming style, and paints the various characters – grizzled Siberians, officious Russian bureaucrats, and mad scientists – with such easygoing charm, that it really doesn't matter. And his cranking of the race-against-time plot is so relentless that it offers little time to reflect on the daftness of the whole thing. (Ultimately it really isn't the point anyway. It's a great ride; and as much an affectionate portrait of a little-seen part of the world as anything else.) The way Porter literally conjures a getaway car out of nothing when his enemies get too close, for example, is brilliant. And the increasingly frantic finale played out on possibly the strangest international border in the world is a masterpiece of suspense and misdirection.

Kolymsky Heights was Davidson's first thriller for 16 years, and he died in 2009 without having produced another. Which is a pity, because one feels if he had produced a few more like this, he really could have been mentioned in the same breath a Le Carré and Deighton.

But, then again, perhaps this book's reputation as a hidden gem is part of its charm. And if you're taking this to the beach this summer, remember to pack your thermals.

• Kolymsky Heights by Lionel Davidson is available as an ebook from the Kindle Store.