The Thirty-Nine Steps

The Thirty-Nine Steps by JOHN BUCHAM is one of the very first thrillers published.
It was first published in 1915.
The point of the novel was to reassure its readers that the war (world war 1)could be won by the British.

In this novel Richard Hannay is warned by an American spy named Scudder that the Greek Premier was going to be assassinated by the Germans to start a war. Later,Scudder died, leaving his mission to stop the assassination to Richard.  Richard traveled throughout England to stop the assassination. As well as being chased by German spies, he was chased by the police because he was suspected of the murder of Scudder. Needles to say, this story should be enjoyed by all.
It is continued by 4 others:

Greenmantle (1916)

Mr Standfast (1919)

The Three Hostages (1924)

The Island of Sheep (1936).

This book is a excellent thriller because it keeps it's readers fascinated. What separates it from the other books of its time is the fact that it was the only book written to reassure as opposed to a book that is written to make people nervous. I particularly enjoyed this book because the mission of the hero changed unexpectedly halfway through the book.
It should take about 1-1.5 hours to read. I would recommend this story to people of  8+ (it does have some gory details and some advanced vocab as well as a plot that can become confusing.) I would recommend that you save this book for a car trip as it will entice you and you won't have to spend your time counting cows and sheep.(Not that I have anything against counting animals as a matter of a fact I think that it is a very good thing to count them: it opens your personal creativity and lets you think for a while, but counting farm animals should be reserved for after your bedtime.)