If you like this, see The Sunset Limited

http://www.imdb.com/title/tt1510938/?ref_=nv_sr_1

Both movies are very similar, a single set and the entire movie is just people talking. Great script, lots to think about, big ideas.

The interesting thing is both movies challenge traditional thinking and encourage the viewer to have an open mind, and as a result they both end up challenging religion and specifically Christianity, which is defined by blind faith and the lack of all reason and thinking.