Adam Hall's Quiller series. Good to revisit every few years and the mechanism of building to a crisis, then starting after the resolution and backing up is fun. Not for everyone though as it's cold war vintage spy stuff. Feels real though, not like Hollywood versin of Bond. Banks of course, Use of Weapons is great. Just hit 51 and finally reading Dune now, so keep that in mind, but would also suggest Cryptonomicon as i have started it several times, put it down and then come back and had to start again several times.... but i find it interesting enough to keep trying!
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