Twelve alien pods land around the world, and a team of scientists are called to communicate with the aliens and see what their purpose is for arriving.
Dr. Louise Banks (Amy Adams) discovers that by learning the language of the aliens, one can see future events. This means that all the scenes featuring Louise's daughter Hannah were not flashbacks, but visions that she saw once she communicated with the aliens. The aliens are bringing their language to humanity because the aliens will need humanity's help in 3000 years time.
Louise manages to avoid a military attack against the aliens after telling General Shang the dying words of his wife to prove her theory after she had seen their later encounter in a vision. The aliens leave Earth, and Louise decides to pursue a relationship with one of her co-workers, Ian Donnelly (Jeremy Renner), since they will become parents to Hannah, even though things will not end well for any of them.