"Blood-C: The Last Dark" is a 2012 anime film that serves as a sequel to the 2011 television series "Blood-C." The story is set in a near-future Tokyo, where the government enforces strict regulations under the Public Security Preservation Law, suppressing freedom of speech and dissent. Saya Kisaragi, the protagonist, is a skilled swordswoman and a Diva, a supernatural being who hunts Chiropterans, monstrous creatures that feed on human blood. Saya seeks revenge against Fumito Nanahara, a manipulative figure from her past who orchestrated the events of the previous series, leading to the destruction of her village and the death of her loved ones.

The narrative begins with Saya infiltrating a secretive organization called Tower, which is linked to Fumito and conducts unethical experiments on humans. She allies with a group of young hackers known as SIRRUT, who oppose the oppressive government and seek to expose its corruption. Together, they uncover the truth behind Tower's activities, which involve creating artificial Chiropterans and exploiting the Public Security Preservation Law to maintain control over society. As Saya delves deeper, she confronts her own identity and the moral complexities of her mission, torn between her desire for vengeance and her duty to protect humanity.

The film explores themes of justice, revenge, and the consequences of unchecked power. Saya's journey is marked by intense action sequences, emotional confrontations, and a climactic battle against Fumito and his creations. The story concludes with Saya making a pivotal decision that reflects her growth and resolve, leaving a lasting impact on the world she seeks to change. The film maintains a dark and suspenseful tone, blending supernatural elements with political intrigue and personal drama.