George Sims was in life a well-known antiquarian bookseller, so naturally he set his first thriller The Terrible Door in the shady world of book-dealers and collectors. On publication it is was famously described as "not so much a whodunit as a who-done-what" and it tells the story of a mild-mannered book-dealer on the trail of some missing literary letters which certain shadowy characters want to possess but no one wants to admit to owning - or ever having seen. This is not a thriller of gunfights, car-chases and cliff-hangers, but rather a spookily atmospheric journey through the underworld of London on the eve of the Swinging Sixties. Sims, who was to elected to the famous Detection Club, died in 1999. During WWII he served in military intelligence in a special communications unit and at the top secret Bletchley Park code-breaking facility