[1]: 221 Until Towards Zero the reader knows nothing of his domestic arrangements (with the exception of a comment in Chimneys, when he mentions that he is "very attached of Mrs Battle"), but this novel reveals that he also has five children, the youngest of whom (Sylvia) unwittingly provides a key clue to the mystery.
In the Hercule Poirot novel The Clocks, the pseudonymous secret agent Colin Lamb is heavily implied to be the son of the now-retired Battle.
He appears as a detective in the following novels: The 1956 play Towards Zero at the St James's Theatre in the West End featured William Kendall as Battle.
Murder is Easy has been adapted for television three times (1982, 2008, 2023), with each one omitting the character of Battle given his minor role in the plot.
The same series had earlier dramatised Towards Zero and Murder is Easy without Battle, although the former replaced him with the new character of Superintendent Mallard, portrayed by Alan Davies.