The last years so one hundred fifty-two hundred, aliens arrive on Earth. And some cunning people, even in their first arrival, were able to come to an agreement with them, fortunately people were ideological and not greedy and asked them for knowledge. But there were a lot of people who wanted to get this knowledge, and the aliens did not differ in high moral principles and trepidation for the only and non-repeatable human life. Therefore, they offered the earthlings a deal.