The events of XCOM 2 take place 20 years after the storyline of the first game of the series. Earth that you will see here takes on a completely different appearance. Now, as a result of the capitulation that the world leaders signed before the alien invasion, the XCOM organization has become the only hope for saving the planet from imminent destruction. Previously, the organization retired, but now its members will have to prove themselves again.
You will have to face the world captured by the aliens. Humans either defected to their side, succumbing to the promises of prosperity and luxurious life, or were killed as a result of their refusal to do this. Now only those who live on the outskirts remain true to themselves and continue to strive for freedom. Only they can crush the enemies, and you are the only one who can lead them.