Dystopia describes the utopia gone wrong, usually in the form of a controlled state - actually quite like Plato's Republic. Or imagine what has become of Cuba - lack of freedoms, threat of violence/imprisonment/loss of income and nationwide poverty. To survive, many assume conformity is utopia/dystopia societies and individuals are stigmatized. Only the top eschalons exhibit individuality and freedom of thought.
Often these societies feature artificial or contrived religions that reinforce the state power. These religions or cultures focus on one's responsibility to the society over themselves and their families. The family unit is often disbanded and a threat to state loyalty.
The state often directly controls or manipulates the economy by deciding what should be produced and how much. In Brave New World, this is created by a control on population numbers and their desires. They are encouraged to value consumerism, to replace instead of repair, to constantly desire. In other works, such as in Asimov's short stories, computers control the world economy. In Kurt Vonnegut's Player Piano, this perfect control over the economy leads to disatisfaction as the populace feels absurdly purposeless denied the ability to work.
Many of these works are set in the future after a world collapse which necessitated the creation of a planned, authoritarian state. Since these stories are set in the future, the control of the society is often enabled by advances in technology.
The hero may come from any social class but typically comes from the extremes in society, either the low/working class or the upper/power class. The hero is often a member and leader of a revolt movement, s/he will perhaps even sacrifice himself for this movement, or humanity itself.
Brave New World