It is the off-stage characters which hook the writer.

I was watching Clare Balding's interesting documentary on C4 about Emily Wilding Davison and it was the story of the jockey which took me off. Summarised in a couple of sentences; apparently he never rode to his previous standard and was haunted by EWD's face, so much so that he committed suicide in 1951. Thirty-eight years later? Now that's a tale to tweak at the curiosity.