Hatsune Miku: Byzantium is a 2014 American CGI-animated/live-action romantic fantasy action horror film distributed by Warner Bros. Pictures. The film was written and directed by Bobby Graham and stars Lacey Chabert as the voice of the title character alongside Yuri Lowenthal as Kagamine Len and Roger Craig Smith as Sonic with actress Angelina Jolie playing the role of Maleficent in addition to providing the voice of Megurine Luka. The film focuses on Miku as she moves in with an all-male group of vampire hunters while on the run from vampires. The film was released on July 3rd in the UK and on August 20th in the United States.
The film begins with a young man finding a piece of paper on the ground outside a block of flats. The piece of paper is apparently one of the story pages that have been thrown to the wind by Miku Hatsune(Lacey Chabert). Realizing that she is one of the mortals, the young man takes her to his house where he explains his life story before telling her that he is a vampire. Upon realizing this, Miku kills him by using her secret ability to consume a vampire's blood on him after stabbing his wrist with a knife.
Later on, she goes to a local strip club where she witnesses another vampire being killed after the vampire attacks a young human teenage girl but she is soon chased out of the club by yet another vampire. Len Kagamine(Yuri Lowenthal) chases the vampire in hopes of preventing it from attacking or hurting her in front of him. He manages to corner the vampire in Miku's apartment and kills it with just one single gunshot. After this, he and Miku pack Miku's things, set fire to the apartment and leave Miku's hometown.
After arriving in his hometown with Miku, Len meets up with his fellow vampire hunters Sonic The Hedgehog(Roger Craig Smith), Shadow The Hedgehog(Jason Griffith), Silver The Hedgehog(Pete Capella), Miles "Tails" Prower(Kate Higgins), Knuckles The Echidna(Travis Willingham), Manic The Hedgehog(Jaleel White), Kyle Broflovski(Matt Stone), Kenny McCormick(Lucas Grabeel), Kaito Shion(Nicholas D'Agosto), Gakupo Kaumi(Ryan Merriman), Kiyoteru Hiyama(Jeremy Renner), Takashi Komuro(Leraldo Anzaldua), Kyon Sasaki(Crispin Freeman), Itsuki Koizumi(Johnny Yong Bosch), Eric Cartman and Stan Marsh(Trey Parker) and Sticks The Badger(Nika Futterman), who is the group's only female member.
Elsewhere in the city, Miku plays the piano at a local restaurant where Haruhi Suzumiya(Wendee Lee), discovers her. Haruhi passes around a teacup and raises some cash for her and even gives Miku her phone number.
Upon leaving the restaurant, Miku meets up with Len and his friends who then take her to their headquarters known to them and many others around them as the Byzantium, a once-thriving hotel that has fallen into disrepair. She quickly adjusts to the life in the hotel with Len and the others beginning to go through with their plan to turn the hotel into a makeshift music studio for her. She even gets home-schooled by Len who privately gives her lessons in the hotel which leads to the two quickly developing romantic feelings for each other. Interested in Len's past, Miku questions Len, who explains how long he has been fighting vampires for while remaining at the age of fifteen years old while she is sixteen despite being a little shorter than him.
The story, narrated by Len and revealed to the viewer in a series of flashbacks, begins during the Napoleonic Wars, where Len, then a normal human being, encounters two Royal Navy officers, the kind and gentle Captain Ruthven(Jonny Lee Miller) and his even more noble subordinate, Midshipman Darvell(Sam Riley). In order to remain fifteen years old forever, Len leaves with Ruthven, who constantly protects him from being harmed by the people that live with him in a brothel.
When Len is turned into an immortal human by a shrine that lies in the room he's staying in, he is provided with weapons by Ruthven and secretly hunts and kills vampires with Ruthven watching him at night. Years later, Len kills a vampire using a combination of weapons and what appears to be tuberculosis, which still leaves him as one of Ruthven's favourites, even when he visits the brothel.
One day, the brothel is visited by Darvell, whom Ruthven had believed to have died years earlier. Darvell explains to Ruthven that he has, in fact, become a vampire. The only way a human can become a vampire or an immortal vampire hunter is by traveling to an unnamed island. The island is home to a being known as "The Nameless Saint" who resides within a small stone shrine. If a human enters the shrine and accepts death, the Saint will kill them and they awaken as a "soucriant"...a vampire or an immortal vampire hunter. Darvell gives Ruthven a map to the island stating that Len is a survivor due to having all the qualities one needs to become a vampire or an immortal vampire hunter.
After Darvell leaves the brothel, Maleficent(Angelina Jolie), who was listening to Darvell's story, breaks into the brothel, shoots Ruthven in the leg, steals the map, makes her way to the island and becomes a vampire. After she awakens, she meets with Darvell whom she takes with her to her lair. She plans on using him to unleash vampires all over the world. As she has had no henchmen, Darvell agrees to be her companion so that she can increase the number of vampires she has had and she warns him that he must always remain at her side and follow her code on pain of death for any violation. Upon hearing this, Len bids farewell to Ruthven and heads out to live a life of his own.
Two centuries later, two years prior to the present day events of the film, Miku is sleeping peacefully when three vampires break into her house and begin to question Miku's family on where Len is. When her brother throws a book at one of the three vampires, hereby killing it, the other two vampires kill the rest of the family, much to the distraught of Miku when she sees the dead corpses of her family and the two vampires that were killed by Len. Miku then spends the next two years running from vampires. She even protects herself from being turned into a vampire by slaying vampires using weapons that range from guns to axes to swords. Her actions effectively impress nearby people.
Back in the present day, Miku assumes that the story is a work of fiction, but Len tells her that it is his life story and from that moment on, the two have romantic moments with each other day and night after day and night, even with Sonic's two teachers hearing about Len's life story from the blue blur himself. Miku begins to believe Len's story and Len offers to turn her into an immortal vampire hunter as he does not want her to die of any illness. Miku has gained Len's true love for her and agrees to let him help her become an immortal vampire hunter so they can be together. Luka Megurine(voiced by Angelina Jolie) is contacted by Sonic's male teacher. Upon hearing from Darvell that Len has revealed his life story to Miku, Maleficent sends a group of vampires to the hotel.
Luka confronts Len at the hotel but Sticks and Haruhi keep telling her that Len had to tell Miku the truth in order to prevent her from getting ill in an attempt to not let her isolate her and keep her from leaving with Len. When the group of vampires breaks into the hotel, the group begins to hold them off. During the battle Kiyoteru is killed and Len traps Miku in an elevator at the hotel to keep her safe. Shadow runs out of the hotel with the intention of killing a vampire that is near Luka's house. Luka goes with him to keep him safe. The remaining vampires go downstairs without killing the other vampire hunters and capture Miku. Len follows Shadow and Luka to Luka's house but leaves after killing the vampire near it when he realizes that Miku is in mortal danger. The vampires, along with Darvell and Maleficent, take Miku into their custody and while driving her to their lair are stopped by Len.
Miku escapes Maleficent's car after killing the vampires with single shots from a gun that she found but Maleficent subdues her on the steps to a ride at a local amusement park. She then hands Darvell a sword to decapitate her. However, Len, who got out of the car's way, snatches the blade, swings it and beheads her, freeing Darvell from Maleficent's spell although he is still a vampire. Darvell tells Len that there are many more vampires in the world and that they will continue to threaten people until Len kills them.
Deciding that he can't remain the leader of the vampire hunters and that he has found it best to be a freelance vampire hunter, Len passes the role of the leader of the vampire hunters on to Sonic before he and Miku part ways with their friends. Darvell asks Sonic if he can join the team of vampire hunters. Sonic decides to allow him to join to which he adds that they have time. The group then head back to their hotel with Darvell whilst watching for any vampires. Len takes Miku to the nameless island and guides her to the ancient shrine and assures her that there's no need to be afraid and that he will wait just outside the entrance to the shrine for her. The film ends with Miku entering the shrine.