Buried

As it turns out the hype was correct! Ryan Reynolds kept the story
going confined in a wooden coffin. Every persons basic fear of
confined spaces and being buried alive was demonstrated in this film.
Limited to a dying cell phone, Reynold's character was able to
transition through the basic phases of death - fear, denial, hope, and
acceptance. The writer didn't even play into the conventional
Hollywood equation of jumping the shark at the end. The film left the
viewer in a confined space much like the coffin and though did not
have the expected endig was still satisfying!