Aliens and humans meet when a flying saucer lands on earth. A humanoid appears from the vehicle and explains that he comes in peace. The military surrounds him, and as he makes an unexpected movement, he is shot. His companion, a robot appears, though the humanoid stops him from hurting them. The shot destroyed the humanoids gift for the president.
The alien is then taken to the hospital though he heals himself. No one manages to enter the saucer. Klaatu wishes to talk to all the world leaders at once, though this is impossible. He then requests to integrate with the humans, which he is not permitted to do. Klaatu runs away and stays at a boarding house.
Klaatu becomes a young child’s babysitter as his parents are away. He goes to some of the people that Bobby, the young boy, looks up to and helps him solve a math problem. Klaatu needs help to save the earth, and is helped by Bobby’s mother, Helen, who breaks up with her boyfriend when he betrays them. Klaatu is shot dead and Helen mutters some words Klaatu told her to say. Klaatu is revived for a few moments where he tells earth that they have two choices, peace or elimination, before he heads back to his country,
