I just completed Epitaph for a Spy by Eric Ambler.

This book is part of Ambler's informal 'amateur sleuth' series, and resembles an Agatha Christie whodunit, set in a hotel on France's Cote D'Azur. The protagonist - a stateless immigrant - finds himself press-ganged by the authorities to unmask a spy among the cast of residents.

I am enjoying the collection, but Ambler is no Agatha, and in this case the development of the various suspects felt somewhat superficial and random. I once heard Melvin Bragg comment that he imagined it would be simple to pen a Christie-like plot - but that when he tried he found it impossible.

Ambler's style is economical and easy to read, and the subject matter - mixed Europeans thrown together during the tense pre-War years - provides an informative insight into the times, and a credible backdrop against which the plot is acted out.