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.
Now in the waning years of his life, the feeble octogenarian, Frank "The Irishman" Sheeran--a former meat driver; powerful president of Local 326 of Delaware's Teamsters Union; ruthless racketeer, and mob hitman--finds himself confined to a wheelchair, forgotten in a nursing home in West Chester, Pennsylvania. Weary but still as-silent-as-the-grave, Sheeran recounts his pivotal first murder; his ties to the notorious Bufalino crime family; the assassination of John F. Kennedy; the energetic crusade of the Attorney General, Robert F. Kennedy, and his alleged connection to the murder of the American labour union leader and President of the International Brotherhood of Teamsters, Jimmy Hoffa. Now, reconciliation is the only means to salvation. What's it like to be the last man standing?