Despite the (selective?) favourable quotes from the Guardian and the Telegraph, this book is most definitely not in the same league as Len Deighton or Le Carre.
For starters, much of the narrative comes straight from the mind of the main protagonist, Paul Dark - in effect we're told the story instead of finding out through the action or characters.
The dialogue is pedestrian - for example when Dark hot-wires a jeep, his female companion comments 'That's a clever trick'; 'It can come in useful', Dark replies. Dull, clunky.
And the plot may be action-packed but it's sub-James Bond stuff, with the heroes using an unlikely ploy to escape from their cell ('somehow I hit home..', 'against all the odds it had worked'), the subsequent helicopter episode ('this was it, this was the end...'), and then the potential drowning scenario ('it looked like some kind of passage..'). It's not quite 'with one bound I was free', but it's not far off it.
I gave up with a hundred pages left, I simply had no interest left!