Greg O’Brien during a 2015 visit to Ireland.Duncannon, County Wexford – The tapering headland of Hook Head on the Irish Sea, at the mouth of rivers Barrow, Nore and Suir, is wholly inspiring in its rugged landscape, primeval history, and the majesty this jagged peninsula evokes. At its rocky tip stands the majestic 800-year-old Hook Head Lighthouse, one of the oldest working lighthouses in the world. It rises like an ancient barbican—four stories high with trademark black and white stripes and limestone walls up to 12 feet thick that will likely stand until end times. Legend has it that long before construction of the lighthouse, monks in the fifth century from the nearby Dubhan monastery lit fires to warn ships from the treacherous red sandstone sarsens.

By hook or by crook, I was destined to connect here, southeast of Dublin, with John Joe Vaughan— two brash Irishmen separated by a sea of blue, roiling waters rushing to a horizon where water flushes up against the sky. It was God-ordained.
I had met John Joe almost nine months earlier at Logan Airport upon my return to Boston from Dublin, an annual pilgrimage to Eire. He had just arrived himself with family to visit his daughter Rena, who now lives in New Hampshire. While I was on the cellphone responding to a queue of backlogged voicemails, Rena began waving at me. She recognized me from a photo in my book, “On Pluto: Inside the Mind of Alzheimer’s.”