In 1944, young Hannibal Lecter is just eight years old, residing in the grand Lecter Castle, built by his ancestor Hannibal the Grim in the serene Lithuanian countryside. Together with his younger sister Mischa, and their parents, they flee to the family's hunting lodge, desperately trying to escape the encroaching German army. Back at the castle, six Lithuanian militiamen—Grutas, Dortlich, Grentz, Kolnas, Milko, and Pot Watcher—seek to join the Waffen-SS. The commanding SS officer orders them to murder the family's Jewish cook left behind, a task they carry out with disturbing enthusiasm.
In a twist of fate, a Soviet tank arrives at the lodge looking for water, forcing the family out. But their moment of reprieve is short-lived; the tank is spotted by a German Stuka bomber, leading to chaos. The bomber is brought down by the tank but crashes into it, triggering an explosion that leaves only Hannibal and Mischa alive from the initial tragedy.
Stripped of their home, the SS militiamen loot Lecter Castle. When Grutas kills their wounded commander and seizes his Iron Cross, they retreat into the woods, ultimately finding the Lecter lodge. With resources dwindling in the harsh Baltic winter, the men turn their hungry eyes toward Hannibal and Mischa, setting the stage for terror.
Fast forward eight years, Lecter Castle transforms into a Soviet-run orphanage. Hannibal, now unable to speak due to the horrors he endured, is taunted by a bully about not singing the orphanage anthem. In a moment of defiance, he uses a fork to fend off an attack, piercing the bully's hand.
As memories of Mischa haunt him, enraged, the youth commander confines Hannibal to a dungeon. In a bid for freedom, he escapes to Paris to live with his widowed aunt, Lady Murasaki-Lecter, who helps him find his voice again and introduces him to the art of flower arrangement, martial arts, and honoring his ancestors.
In a local market, after facing a butcher's racist insult directed at Lady Murasaki, Lecter's restraint wears thin. He confronts the butcher later, demanding an apology, which is met with hostility. Overwhelmed by rage, Hannibal uses a katana, brutally exacting revenge by slicing the butcher and finally decapitating him. Later, an insightful family cook tells him about the fish's most tender morsels, contributing to Lecter's unsettling culinary skills that involve biting off victims’ cheeks.
As Inspector Popil, a detective grappling with his own grief from the war, investigates the butcher's murder, Lady Murasaki helps Lecter evade suspicion by displaying the butcher's head outside the police station during Hannibal's questioning.
Eventually, Hannibal secures a spot as the youngest medical student in France, where he gets involved in cadaver preparation. Witnessing the execution of a war criminal, he injects himself with a sodium thiopental solution in an effort to recall his sister's tragic fate while listening to Glenn Gould's rendition of the Goldberg Variations, an iconic piece also present in Silence of the Lambs. His jarring memories drive him back to Lithuania, determined to unearth dog tags and the remains of his sister.
Crossing into Soviet territory, Dortlich, now a border patrol agent, spots Lecter. In excavating the lodge ruins, he unearths the dog tags of his sister's murderers. A fight ensues, where Hannibal triumphs over Dortlich and forces him to disclose information about his accomplices before gruesomely executing him.
With vengeance on his mind, Lecter seeks out connections with Kolnas, a member of the gang. Despite his intentions, he refrains from killing Kolnas for the sake of his children, but the pressure intensifies as Grutas, evolving into a sex trafficker, hires another member, Zigmas Milko, to eliminate him. Lecter, aware of Milko's approach, asserts his dominance, ultimately sealing Milko's fate in a gruesome manner.
In a tense moment, Grutas kidnaps Lady Murasaki, luring Lecter into a trap. Hannibal cunningly uses Kolnas' emotions against him, forcing him to divulge information. Betrayed by his own actions, Kolnas meets a grim end at Lecter's hands.
In the climactic confrontation with Grutas, tensions soar as secrets are unraveled. Lecter, cultivating a newfound rage, inflicts gruesome punishment, leaving an indelible mark on Grutas. After the houseboat is engulfed in flames, Lecter, presumed dead, emerges from the shadows, now unchained in a chilling pursuit across Canada, intent on hunting down the last of his sister's assailants, Grentz. This harrowing saga concludes, seamlessly stitching the fabric of Lecter's dark legend as he eventually makes his way to America, setting the stage for further chaos and mayhem.
