Just a glass to quench your thirst.
A worldwide chemical warfare resulted in most of the world's water being contaminated, BEYOND PURIFICATION.
You're a spy working along side a rebel organisation trying to put an end to a repressive, authoritative regime.
The non-linear gameplay gives the player the freedom to chose his own playstyle and ways to accomplish an objective.
Completing side quests provides tactical advantages, thereby, weakening certain bases of operations through out the map.
Weapons can be modified and upgraded via. attachments which can be purchased or found during the course of the game. The type of unlockables you get greatly depends on your playstyle.
Gadgets like the 'Hacking Tool', used to unlock doors or hack into servers and databases and the 'Speech Analyser', used to decipher enemy messages and other gadgets like such can be purchased as the player progresses through the game.