The narrative of Frankenstein is framed by Victor Frankenstein telling his story to Captain Anderson on a ship trapped in the Arctic. The film then hinges on a crucial structural shift: halfway through, the Creature boards the ship and takes over the narration, presenting his own version of events. This reveals Victor to be an unreliable and self-serving narrator. We learn the Creature's violence was not random; for example, the death of Victor's brother William (Felix Kammerer) was accidental, a result of William attacking the Creature in fear.
A major plot point involves Victor's benefactor, Henrich Harlander (Christoph Waltz), who reveals he is dying of syphilis and funded the experiment with the selfish intention of having his own brain transplanted into the new, perfect body. Victor refuses. The film's most significant departure from the novel is its ending. Elizabeth is not killed by the Creature; she is shot and killed accidentally by Victor, who is trying to shoot the Creature. In the Arctic, Victor doesn't die consumed by hatred. Instead, he and the Creature achieve a form of reconciliation. Victor, finally understanding the depth of his failure, apologizes for his abuse and abandonment. The Creature, in turn, forgives his creator just before Victor succumbs to his injuries. Unlike the novel, where the Creature plans his own suicidal immolation, this version establishes that the Creature is immortal and cannot die. The film ends not in tragedy and death, but with a bittersweet image of hope: the immortal Creature, alone but free from the cycle of vengeance, choosing to live on as the sun rises, embodying the final quote from Lord Byron: "The heart will break and yet brokenly live on."