After the war McNeile left the army and continued writing, although he changed from war stories to thrillers. In 1920 he published Bulldog Drummond, whose eponymous hero became his best-known creation. The character was based on McNeile himself, on his friend Gerard Fairlie and on English gentlemen generally.

McNeile interspersed his Drummond work with other novels and story collections that included two characters who appeared as protagonists in their own works, Jim Maitland and Ronald Standish. He was one of the most successful British popular authors of the inter-war period.

Bulldog Drummond
The Black Gang
The Third Round
The Final Count