Great thread! i read widely, but especially love mysteries and espionage for escape (Alan Furst is wonderful!). Here are two under the radar that merit sampling. Peter May is a gifted writer. I got interested in him because of his three mysteries that take place in the Scottish Hebrides (where we're going this summer). Wonderfully evocative stuff. Also the great Japanese mystery writer, Keigo Higashino, whose works (so far as I can judge, which means not at all) are splendidly translated: morally and intellectually engaging. I'm always looking for out-of-the-way espionage/mystery writers, as I go usually go through their entire corpus in a couple of weeks. So, please suggest!! Thank you, Bonpland: I just bought the latest McKinty on Kindle because of you!
Just to say for "tough guy" writing under the radar (not the obvious Ross McDonald, Hammett, etc) my all-time fav is Donald Westlake's Parker series. Read them in order. He's a very very bad man....
And another series that could take several years is Patrick O'Brian's Master and Commander, etc.. If you like the first, you will like all 20 of them.
The last time I was envious of people who hadn't yet read something that I had already finished were the two (final one in the works) great books on Thomas Cromwell by Hilary Mantel that form the incredible BBC Wolf Hall TV series. Not easy reading at the beginning, but once you get used to her style, positively enthralling. Read the books, then see them faithfully adapted. An amazing treat.