One for the horror fans, you all have no excuse not to see this.
This a Spanish film first of all, so you'll be reading subs. Also it's filmed Blair-Witch Project style, or more recently- Cloverfield style. The story follows an unfortunately irritating night time TV show host Angela and her cameraman Pablo as they document what the hell goes on in a Firestation. During this the station gets a call about a person trapped in an apartment and Angela and Pablo goes along with the dispatched officers to see what's up. What they find is a weird old lady...who starts attacking people. When they try to leave, they find that the building is sealed of and quarantined by Army Special Forces, trapping everyone inside. What takes place in the apartment building after that is one awesome scarefest (especially the last few mins).
By the way, this movie is being given a US remake called 'Quarantine' which will be released later this year...but we all know how those remakes turn out.