Bats in the Belfry A London Mystery 

By E C R Lorac

An intricate murder systery set in 1930s London, by a classic writer from the Golden Age of detective stories. 

Death in Fancy Dress

By Anthony Gilbert

This story involves the British Secret Service working to uncover a large blackmail ring, in events which take place in a classic country house setting. This novel was first published in 1933.