Although the contrive of the movie is very good and it is fascinating to see what little things can leverage which way a decision goes, where this movie actually succeeds is in presenting the characters of the 12 jurors.
Juror #1 - a simple man who apparently does not understand the full complexity of the task that lies before him but is seeking to manage everything not to let any individual else find this out.
Juror #2 - a small, rather man, apparently unaccustomed to giving his own attitude much less to anticipating ...