The entire prison staff is hostaged inside the prison they are guarding. All of the prisoners, especially those who have a deep grudge against Batman, are in control.
The game is said to be in 2.5D metroidvania style with free-flowing combat. In the trailer, you can see some of Batman's worst and mortal enemies such as Black Mask, Penguin and Joker. Catwoman also makes an appearance in what seems to be a team up with the Dark Knight.
Batman Arkham Origins: Blackgate is releasing for the Nintendo 3DS and PlayStation Vita on October 25th together with its console counterpart.