After the destruction of the dreadnought, tensions between XCOM and the Council are higher than ever. Despite growing opposition and oversight, the Commander doesn't hesitate to push humanity further into uncharted territory, as well as dealing with an ancient global conspiracy, and a growing number of countries looking to take advantage of an invasion that is only just beginning.

When aliens begin an invasion of Earth, the XCOM project is activated in a desperate attempt to slow the incursion and save humanity. With few options, the Council turns to the only one who will do whatever it takes to defend humanity. Now, the war criminal known as the Commander must rally the defenders of Earth while contending with his enemies within the United Nations.