The author of The Road Less Traveled and People of the Lie gives a straightforward account here of two exorcisms he did. There’s no proof the devil here, exactly, but pretty good evidence.
I’ll note here a piece in the Washington Post‘s Outlook section, “As a Psychiatrist, I Diagnose Mental Illness/Also, I Help Spot Demonic Possession,” by Richard Gallagher, July 3, 2016, at B1. And, speaking of the Washington Post, the late Justice Antonin Scalia (see the recent compendium of his speeches, Scalia Speaks, at pages 112-13) recounts how the paper sent its journalists to cover reports of weeping statues and a local Catholic priest with stigmata; the reporters “produced a strange story about the phenomenon …: they obviously did not want to appear so unsophisticated as to believe this nonsense, but neither could they find any explanation for it. As far as they could tell, the young priest was not a charlatan, and puddles of water did indeed appear at the feet of the statues.”