Dystopia

A dystopia is the opposite of a utopia, and can mean a utopia that has become corrupt. This can be seen in George Orwell's book "1984". and Aldous Huxley's book "Brave New World". A dystopia often has many problems, such as poverty, pollution, or a cruel ruler. 
A frequent theme is a place that is supposed to be a beautiful and perfect utopia, but where something unforeseen ruins it.