Six hours on a cramped red-eye from Boston had Donovan in a foul mood—jumpy and irritable. He’d resisted this journey for 18 years; never thought he’d find himself back in Ireland with this mission. Still, he reasoned, if things worked out, this would be the first and last time he’d have to make the dreadful trek. For a man who hated to travel, once was plenty. All the more reason to make this one count.

He’d been jerked from a semi slumber by the screech of the landing gear on the Aer Lingus jumbo jet, slicing through the dense fog over Shannon airport. His wristwatch—which he’d set five hours ahead—showed “5:45 A.M., February 3, 2005,” as he vaguely tuned in the faux-British accent of the young stewardess prepping the passengers for landing.