The catalyst, as it wobbles up and triggers the chain of actions and reactions, is that the young man Tommy returns home to Pittsburgh. A regular evening when his father Paddy has been on an AA meeting and listened to the audio book of Moby Dick while he was driving home in the dark, he finds his youngest son on the steps to his front door. (Republishing old draft. Sorry for the spelling/grammar errors, feel free to correct them.)
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