James Fenimore Cooper & E. Phillips Oppenheim 
10 Must-Read Spy Novels [EPUB ebook] 
The Secret Agent, The Web, The Great Impersonation, The Spy, Who Goes There, I Spy, The Nine Unknown

This anthology presents a selection of the best espionage novels from renowned authors, each contributing a distinctive voice to a genre that explores the shadows of international intrigue and undercover operations:
’The Secret Agent’ – Joseph Conrad’s exploration of anarchism and espionage in London sets a grim tone for spy literature, echoing the political tensions of the time.
’The 39 Steps’ by John Buchan – In this adventure espionage classic Richard Hannay is buttonholed by an American stranger who knows of an anarchist plot to assassinate the Greek Premier during his forthcoming visit to London. It is now up to Hannay to save the day and stop Europe from destabilizing.
’The Great Impersonation’ by E. Phillips Oppenheim – German Leopold von Ragastein meets his doppelganger, Englishman Everard Dominey, in Africa, and plans to murder him and steal his identity in order to spy on English high society just prior to World War I. However, doubts of the returned Dominey’s true identity begin to arise.
Who Goes There? by B. K. Benson is a tale of a spy in the midst of American Civil War. The young man from New England has a specific brain condition that causes him to lose memory every once in a while. His knowledge about the South qualifies him to spy for the Union, but his brain plays a trick on him once again. While in a Confederate uniform, he gets amnesia and ends up fighting for the South.
’The House of Spies’ by Warwick Deeping – Anthony Durrell is a man of colorful past who lives in an old Stonehanger House with his daughter Nance. On the eve of Napoleonic Wars a ring of French spies created the spy web in England and nobody could be trusted. One evening, the Durrell’s are upset by sudden arrival of a wounded stranger Jasper Benham, which causes turmoil and disorder at the old Stonehanger, revealing some things from old Durrell’s past.
’The Nine Unknown’ by Talbot Mundy delves into hidden societies and ancient secrets, giving a fresh twist on modern espionage by intertwining mysticism with spy craft.
In ’Annette, the Metis Spy’ J. E. Collins explores tensions in Canada during the colonial era, showcasing how local figures played crucial roles in larger conflicts.
’Walker of the Secret Service’ – Melville Davisson Post’s narrative brings to life the secret service activities of an agent in the early 20th century, highlighting the complexities of domestic and foreign concerns.
’The Spy’ is a tale about counterespionage set during the Revolutionary War, with main character Harvey Birch, British loyalist who is in fact a George Washington’s spy. James Fenimore Cooper’s work reflects early American attitudes towards espionage, painting a portrait of personal loyalty amidst the backdrop of national identity.