Michael Shaeffer is a retired American businessman, living peacefully in England with his aristocratic wife. But her annual summer party brings strangers to their house, and with them, an attempt on Michael's life. He is immediately thrust into action, luring his lethal pursuers to Australia before venturing into the lion's den - the States - to figure out why the mafia is after him again, and how to stop them.

Eddie's Boy jumps between Michael's current predicament and the past, as we glimpse the days before he became the Butcher's Boy, the highly skilled hit man who exacted revenge on some double-crossing clients and started a mob war. He's meticulous in his approach as he attempts to pit two prominent mafia families against each other to eliminate his enemies one by one. But will he be able to escape this new wave of young contract killers, or will the years finally catch up to him?