Humans and robots coexist in the tri-layered city of Metropolis, although robots are discriminated against and segregated to the city's lower levels. Most of Metropolis' human population is unemployed and deprived, and many people blame the robots for taking their jobs.

Duke Red, the unofficial ruler of Metropolis, has overseen the construction of a massive skyscraper called the Ziggurat, which he claims will allow mankind to extend its power across the planet. A wayward robot disrupts the Ziggurat's opening ceremony, only for Rock, Duke Red's adopted son-(who was orphaned after losing his family during a previous war) and the head of the Marduk Party, a paramilitary organization aiming to promote anti-robot sentiments, to shoot it down. Meanwhile, Private detective Shunsaku Ban and his young nephew/assistant Kenichi Shikishima travel from Japan to Metropolis to arrest Dr. Laughton, a rogue scientist wanted for organ trafficking and human rights violations. Unknown to Shunsaku, Duke Red has hired Laughton to build an advanced robot modeled and named after Red's deceased daughter Tima. Red intends to use Tima as a central control unit for a powerful secret weapon hidden in the Ziggurat. However, an envious Rock learns of Tima's existence and, fearing for his father's safety, shoots Laughton and sets fire to his laboratory.

Shunsaku encounters the burning laboratory and discovers the dying Laughton, who gives Shunsaku his notebook. Meanwhile, Kenichi finds the activated Tima. The two fall into the sewers and are separated from Shunsaku. While Shunsaku searches for his nephew, Kenichi and Tima search for a way back to the street level. They grow close as Kenichi teaches Tima how to speak, both unaware she is a robot. Rock and his subordinates hunt them relentlessly, and the pair encounter a group of unemployed human laborers who stage a revolution against Red.

The president and the mayor of Metropolis try to use the revolution to overthrow Red and gain control of Metropolis, but the president's top military commander, General Kusai Skunk, who has sided with Red, assassinates them. Red then imposes martial law to suppress the revolution. After the failed revolt, Kenichi reunites with Shunsaku, but Rock, who reveals Tima as a robot, wounds him. However, Red disowns Rock and strips him of his command of the Marduks for attempting to kill Tima. Duke Red takes Tima away to the Ziggurat.

Still determined to eliminate her and regain his father's affection, Rock kidnaps and deactivates Tima, who is now confused about her identity. Shunsaku rescues her and, after following instructions from Laughton's notebook, reactivates Tima. The two discover Kenichi is being held in the Ziggurat, but Duke Red and the Marduks then capture them while the pair are en route. Brought to the top of the Ziggurat, Tima confronts Duke Red about whether she is a human or robot. Duke Red tells her she is a "superhuman" and destined to rule the world from her throne. Disguised as one of the Ziggurat's maids, Rock shoots Tima, exposing her circuitry.

Horrified by her true identity, Tima goes insane. She proceeds to sit on the throne, ordering a biological and nuclear attack on humanity. While the others flee, Kenichi tries to reason with Tima. Robots drawn by Tima's command attack Duke Red. Not wanting "filthy robots" to kill his father, Rock kills himself and Duke Red in a massive explosion. As the Ziggurat starts to collapse around them, Kenichi finally reaches Tima and separates her from the throne. Seemingly lost, Tima tries to kill Kenichi, but falls off the tower in the struggle. Out of love for her, Kenichi tries to save Tima and pull her up using one of the cables still grafted to her. As the cable begins to fray, Tima remembers the time Kenichi taught her language and asks Kenichi, "Who am I?", before she loses her grip and falls to her presumed death. The Ziggurat collapses, destroying a large part of Metropolis.

Afterwards, Kenichi searches the ruins and discovers a group of robots have salvaged some of Tima's parts in an effort to rebuild her. While Shunsaku and many other human survivors are evacuated, Kenichi chooses to remain behind; he eventually rebuilds Tima and opens a robot workshop.

https://en.wikipedia.org/wiki/Metropolis_(2001_film)
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