Wiktionary
play old harry
vb. (context idiomatic English) To play the devil; to make mischief.
Usage examples of "play old harry".
The Sophie lay off San Pedro: she had been extraordinarily busy this last week, and she was rapidly perfecting her technique, staying well over the horizon by day, while the military forces of Spain hurried up and down the coast looking for her, and standing in at night to play Old Harry with the little ports and the coast-wise trade in the hours before dawn.
He would miss them both - they had engaged his affections - but he could scarcely wait for them to be gone, carrying the poison, harmless to Wogan, that would play Old Harry with Buonaparte's intelligence system, and saving Wogan herself from the dreariest exile.