OZ is an old TV series released by HBO. It shows the life in one security prison called Oswald, but the main plot is focused on Emerald City, which is one of the prison levels.<br /><br />Oz have an amazing plot and an outstanding cast! There are many of characters and almost all of them are very interesting. Basically they are divided in groups (gangs), the Sicilians, the Black people, the Aryans, the Gays, the Latinos and many others who doesn't have any specific group, but deal with many others like Ryan O'Reily (The Irish).<br /><br />The plot is very well built, there are a lot of conspiracy inside, a lot of fight for the power. But all of this is not just exposed in form of violence, all is very intelligent and smart, nothing happens without a reason, all is connected and very interesting to guess! I really love this series, and who wanna see something intelligent, very well produced with a very good cast and performances, MUST see OZ!