Bentley was born in London and educated at St Paul's School and Merton College, Oxford.

[1] His detective novel Trent's Last Case (1913)[5] was much praised, numbering Dorothy L. Sayers among its admirers, and with its labyrinthine and mystifying plotting can be seen as the first truly modern mystery.

He contributed to two crime stories for the club's radio serials broadcast in 1930 and 1931,[6] which were published in 1983 as The Scoop and Behind The Screen.

G. K. Chesterton dedicated his popular detective novel, The Man Who Was Thursday, to Bentley, who was a school friend.

This is the recently re-discovered "Flying Visit", published in the Evening Standard on 31 March 1953.