Hello! Allow me to help!
Your question: Summary on "arrival" movie
My answer: Linguistics professor Louise Banks (Amy Adams) leads an elite team of investigators when gigantic spaceships touch down in 12 locations around the world. As nations teeter on the verge of global war, Banks and her crew must race against time to find a way to communicate with the extraterrestrial visitors. Hoping to unravel the mystery, she takes a chance that could threaten her life and quite possibly all of mankind.
Why is my answer correct? Good question! Allow me to explain: Linguist Louise Banks's daughter, Hannah, dies in adolescence from an incurable illness.
Twelve extraterrestrial spacecraft hover over disparate locations around the Earth. A U.S. Army officer, Colonel G.T. Weber, recruits Banks and physicist Ian Donnelly to find out why the aliens have come. Weber takes them to an army encampment in Montana near one of the craft. On board, Banks and Donnelly make contact with two seven-limbed aliens, whom they call "heptapods"; Donnelly nicknames them Abbott and Costello. Banks and Donnelly begin researching their written language of complicated circular symbols. As Banks studies the language, she starts to have visions of a child, who seems to be her daughter.
When Banks is able to establish sufficient shared vocabulary to ask why the aliens have come, they answer: "Offer weapon". However, China translates this as "Use weapon", prompting them to break off communications, and other nations follow. Banks argues that the symbol interpreted as "weapon" might mean "tool", and that China's translation likely results from the competitive nature of their interaction with the aliens.
Rogue soldiers plant a bomb in the Montana craft. Unaware, Banks and Donnelly re-enter the alien vessel, and the aliens give them an extremely complex message. Just before the bomb explodes, one of the aliens ejects Donnelly and Banks, knocking them unconscious. When they reawaken, the military is preparing to evacuate, and the craft has moved out of reach.
Donnelly discovers that the symbol for time is present throughout the message, and that the writing occupies exactly one-twelfth of the space in which it is projected. Banks suggests that the full message is split among the twelve craft, and the aliens want all the nations to share what they learn.
China's General Shang issues an ultimatum to the aliens, demanding that they leave within 24 hours. Russia, Pakistan, and Sudan follow suit. Communications between the international research teams is terminated as worldwide panic sets in.
Banks goes alone to the craft, and it sends down a transport pod. One of the aliens is dying from the explosion; the other explains that they have come to help humanity, for in 3,000 years they will need humanity's help in return. The "weapon" is their language, which changes humans' linear perception of time, allowing them to experience "memories" of future events. Banks's visions of the child are actually premonitions of her future daughter, Hannah.
Banks returns to the camp as it is being evacuated and tells Donnelly that the alien language itself is the "tool". Reflecting the Sapir–Whorf hypothesis of how linguistics shapes perception — mentioned earlier by Banks — those who master it are able to perceive the future and past. She has a premonition of a United Nations event, in which Shang thanks her for having convinced him to call off the attack by calling his private number and reciting his wife's dying words: "In war there are no winners, only widows."
In the present, Banks steals a satellite phone, calls the number, and recites the words. The Chinese announce that they are standing down and release their twelfth of the message. The other countries follow suit, and the twelve craft depart.
During the evacuation of the camp, Donnelly expresses his love for Banks. They talk about life choices and whether he would change them if he could see the future. Banks knows that she will agree to have a child with him despite knowing their fate: that Hannah will die, and Donnelly will leave them after she reveals that she knew this.
Hope this helps! UwU
-Maxwell