THE PRISONER by Alex Berenson, Putnam.

The Prisoner will have you defying your drooping eyelids to keep reading way too late into the night

– it’s a masterclass in story-telling. While former CIA agent John Wells is learning of the existence of an agency mole, his offsider, Ellis Shafer, is watching drone footage of two colleagues die in the field. The mole, who calls himself Wayne, is confessing his doubts and crimes to himself and planning further atrocities. And an Islamic State chemist is cooking up a batch of the deadly gas, sarin, and experimenting on unfortunate prisoners. As these plots become interwoven and the violence escalates, the pages turn themselves. The climax more than pays off, although the ending is abrupt, leaving you with the sudden deflation you feel from the inertia of a braking rollercoaster.