It's 1944 and young Hannibal Lecter (AARON THOMAS) is a happy kid living with his family in Lithuania. But WWII soon encroaches, forcing them from their castle to a remote home in the woods. Yet, they're not safe even there, and a battle between a Russian tank crew and a German fighter results in everyone in his family being killed, save for his younger sister, Mischa (HELENA-LIA TACHOVSKA).
They must then contend with the arrival of a small band of war opportunists led by Vladis Grutas (RHYS IFANS) who take cover in the kids' home and plan to use the children as an alibis should soldiers from either side confront them. With the food now gone and their hunger increasing, Grutas and the others, including Kolnas (KEVIN McKIDD), Dortlich (RICHARD BRAKE), Milko (STEPHEN WALTERS) and Grentz (IVAN MAREVICH), decide to kill and eat Mischa, a development that will forever haunt her brother.
Years later, Hannibal (GASPARD ULLIEL) escapes from the orphanage run in his former home and makes his way to Paris where he finds that his uncle is dead, but his Japanese aunt, Lady Murasaki (GONG LI), takes him in and teaches him various things, including culture, how to survive, and the ways of the samurai.
Having been changed forever by the actions of Grutas and the others, Hannibal takes out his pent-up anger on a butcher who's been acting lewdly toward his aunt. That sparks the interest of Nazi war criminal hunter, Popil (DOMINIC WEST), but the police inspector can't prove the increasingly cunning and unflappable young man's involvement with the murder.
With his bloodlust now energized, and with the knowledge gained from attending medical school, Hannibal then sets out to get revenge on those who killed and ate his sister, all as his aunt tries to figure out how to react, and Popil tries to catch him in the act.