It's a really nice idea that is ruined by poor acting and some stupidly ridiculous reasoning (the whole thing about being a prisoner for a start). The attempt at a modern day social and political commentary is very poor indeed: It is not subtle in the slightest and made me cringe more than once.
The ending is just completely stupid. All that security and still a massive part undefended right into the building. Overall, this film is an abortion. It is an extremely dumb film masquerading as an intelligent film. No redeeming points at all.
(Sorry, trying to be vague with the details to avoid major spoilers for this unfortunate enough to want to see it).