Eeyn has asked me to list more of my favorite British thriller writers from the '60s, and since the list is too long for a comment, I'm sorry to have to distract from Harley's Book Forum by making a diary entry of it. I haven't included mystery writers from the period unless their work also includes the spy/crime thriller/adventure genres. Arguably, Eric Ambler and Graham Greene were its modern godfathers, but it was John Le Carre's 1961 "Call For the Dead" that launched the hardboiled Cold War novel craze. I'm not including them on this list, since you've probably all been exposed to them already. Props to Michael Crichton, btw, whose early "Venom Business", as John Lange, was a wonderful evocation of swinging-60s London. Another Yank, RV Cassill, wrote the finest novel about the Profumo Affair, "Dr Cobb's Game".

The rest:

Alding, Peter
Ashford, Jeffery
Bagley, Desmond--a huge favorite and a vastly underrated novelist. His "Flyaway" contains one of the best descriptions of Tuareg life in the Sahara I've ever read. He based all his books on first-hand experience, and provides a great guide to 60s Scandinavia in several of them.
Ball, Brian--SF writer who began as spy/thriller writer
Benton, Kenneth
Canning, Victor--a prolific writer and close friend of Eric Ambler, his career spanned 4 decades. Most of his spy/thrillers were written in the 50s and 60s, his Arthurian "Crimson Chalice" Trilogy in the late 70s.
Davidson, Lionel AKA David Line--I can't say enough good things about this writer. Except that he doesn't write enough.
Cory, Desmond--an excellent, if over-intellectual, writer of the genre, his early novel "Night Hawk" was a retelling of the Orestiad as modern terrorist murder thriller.
Deighton, Len-- the stylistic master of the genre, his Harry Palmer novels and movies are classics. His later trilogies became a bit soap-opera-ish , but still were capable of brutal, hard-edged action and ineffable dialogue. His histories of WWII are a vastly underestimated work.
Gordon, Rex--pseudonym of S.B. Hough, St Louis-born Hollywood screenwriter, who nevertheless produced some good British crime thrillers, as well as SF and hard-core porn.
Haggard, William--former spy who wrote a staggering number of spy novels featuring "Colonel Russell". His writing style is godawful and much of his action is simple wish-fulfillment, but constant non-public details about figures like Marshal Tito or Allende make his books worth wading through.
Hall, Adam, AKA Elleston Trevor--the working man's James Bond, his hero Quiller is probably the toughest spy of them all, and Hall's series provides a how-to manual for the real-life art. Essential reading for lovers of the genre. And should be for CIA applicants.
Hart-Davis, Duff--this cousin of the royals mostly writes non-fiction, with the occasional thriller. His "heights of Rimring" is a perfect companion to Davidson's "Rose of Tibet."
Harvester, Simon--his "Road" novels, featuring Bond-like Dorian Silk, are a classic if overlooked series in the genre.
Healey, Ben-- quirky and off-beat, able to turn an intrigue among art-thieves in Venice into an eccentric romantic thriller.
Household, Geoffrey--with a career spanning 5 decades (!), this prophet of the self-reliant lone hero wrote in every genre imaginable. His "Rogue Male" and "Watcher in the Shadows" helped invent the modern action thriller.
Innes, Hammond--the definitive action-adventure writer of over 30 novels, his "Isvik" is perhaps the most perfect mystery/adventure/seafaring/political thriller ever written, and would make a great SF rewrite. Frank Herbert thought enough of "Doomed Oasis" to use it as the skeleton of "Dune".
Jeffreys, JG
Kyle, Duncan--the master of the complex plot, no one could write a thriller better. Third only to Innes and Bagley at writing adventure, his relentless "Semenov Impulse" and darkly cynical "Black Camelot" are favorites.
Mantell, Laurie
Ross, Angus--editor-turned-writer of hardboiled spy fiction, Ross evolved the purest prose of them all. His hero is another Quiller type, but with less interesting assignments.
John Rossiter AKA Jonathon Ross-- excellent Quiller-like spy-action.
Rutherford, Douglas
Shute, Nevil--a titan in the genre, his novels were to aviation what Innes' were to sailing. Once one of the world's bestselling novelists, almost all of his books bear rereading.
Sims, George--the definition of offbeat, Sims wrote about antique dealers as crime/thriller heroes. Most of them were former boxers. His characters and dialogue are an unmitigated joy. His work was liberally ripped off for the Lovejoy series.

BTW, most of these are long OOP. I have e-book copies of a number of them, which I will send along on request.

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