In Vigilance you play as the totalitarian dictator of an orwellian dystopia. Contrary to what some might think, you really CAN see everything. Or can you? Keep your citizens from revolting against you as long as possible using the vast resources and strong arm of your regime.
Thought-Criminals will periodically spawn, and you need to click on them to arrest them before they march on your buildings. Build military buildings to gain Police presence, Airstrikes, and Bioattacks to defend your regime, and build propaganda mills and youth centers to keep your citizens in line.
The game ends when the people are victorious over your despotic state and depose you, probably to start a democracy or something.