An team of aliens comes to Earth to study the planet.

A group of aliens land on the planet with the intent of studying the planet for scientific purposes. The humans agree to their wishes and allow them to do what they want as long as they don't do any harm or damage. So the aliens create a research site and begin what they came to do.

First they inspect the air. They realize that the air of the planet not clean enough and is full of viruses. The humans tell them that it is due to a large population and their immune systems safeguard them.

Then they check the city water and find out that it is contaminated and not suitable for drinking. This lowers their opinion of the human world.

Soon after the humans find out that the aliens have left without informing them and find a note where they were stationed. It reads: "We have found out that an abnormality is being seen in increasing numbers in the local human populations. We have left for we are afraid of this planet and will never come back."

The humans have only one thing to say to themselves, "Maybe we shouldn't have let them stay in Rio."