Rec 2
The first Rec was both a very good as “zombie” movie and for being a “found footage” film. You never thought that these people under duress were silly for continuing to film themselves being attacked and killed. Rec 2 also does a good job explaining the cameras with Aliens style military helmet cams. In a pretty cool way, the film picks up literally right after the events of the first movie. Much of the suspense and tension is dependent on you having seen the first film and knowing what is lurking in that penthouse apartment. However, the film does kinda fall apart about halfway through when you are introduced to a group of idiot teenagers, but by then I was hooked and just held my nose just so I could reach the finale.