I read this book as a part of my desire to read all of the Edgar Award winning novels. The Light of Day won the Edgar Award for Best Novel in 1964.
The story was later made into the movie, Topkapi.
"Eric Ambler is often said to have invented the modern suspense novel. Beginning in 1936, he wrote a series of novels that introduced ordinary protagonists thrust into political intrigue that they are ill-prepared to deal with. These novels were touted for their realism, and Ambler established himself as a thriller writer of depth and originality. In the process he paved the way for such writers as John LeCarre, Len Deighton and Robert Ludlum." - book cover