Extract the answer to the following question from the movie plot. If the question isn't answerable, please output "Can't answer". Question: Who does Rotwang kidnap? Title: Metropolis Movie plot: Humans and robots coexist in the futuristic city of Metropolis, although robots are discriminated against and segregated to the city's lower levels. A lot of Metropolis' human population are 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 to be shot down by Rock, Duke Red's adopted son and the head of the Marduk Party, a vigilante group whose aim is to calm anti-robot sentiments. Private detective Shunsaku Ban and his nephew Kenichi travel to Metropolis to arrest Dr. Laughton, a mad scientist wanted for organ trafficking. Unknown to Shunsaku, Duke Red has hired Laughton to build an advanced robot modeled and named after Red's deceased daughter Tima. Red intends for Tima to function as a central control unit for a powerful secret weapon hidden in the Ziggurat. However, Rock learns of Tima's existence and, not wanting a robot to overshadow Red, shoots Laughton and sets fire to his laboratory. Shunsaku comes across 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 the street level. They grow close as Kenichi teaches Tima how to speak. Neither are aware she is a robot. The two are hunted relentlessly by Rock and his subordinates, and 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 they are assassinated by the president's top military commander, General Kusai Skunk, who has sided with Red. The duke then imposes martial law to suppress the revolution. In...
Answer:
Maria