After being dumped at the altar on her wedding day, Maggie Conway moves to the island town of Friday Harbor in Washington State, where she meets Mark Nagle, the local coffee shop owner.

Pennsylvania, 1956. Frank Sheeran, a war veteran of Irish origin who works as a truck driver, accidentally meets mobster Russell Bufalino. Once Frank becomes his trusted man, Bufalino sends him to Chicago with the task of helping Jimmy Hoffa, a powerful union leader related to organized crime, with whom Frank will maintain a close friendship for nearly twenty years.