The most affecting section of the play for me - the only truly poignant moment, but a very good one - comes when Emily joins the dead. The review/consideration of the precious nature of life is well wrought here. The powerlessness of nostalgia to overcome the limits of life, I think, is clear and this idea is also rather universally relatable.
I think it's the scene where Emily goes back to visit, so to speak, her twelfth birthday--an important but not too important day from her past.
It's heartbreaking, I think, to watch her try to get her parents to really pay attention to each moment of the day. "Oh, Mama, just look at me one minute as though you really see me....Mama, just for a moment we're happy. Let's look at one another." True confession--even typing this now gets me a little teary-eyed.
The "Everyman" quality of the play certainly speaks to many audience members on perhaps a more accessible level. But, in my mind, one of the most emotional and moving (not to mention morbid) aspects of Act III is the very idea of speaking to the dead. Visually, the scene of a cemetery and all of these passed souls sharing their insight and reflections forces the audience to contemplate what such individuals in their own lives might say and/or suggest about them. Good literature not only places us in the shoes of a character to live vicariously through them, but good literature also forces us to examine our lives and experiences from new perspectives and through new eyes. To me, this is what Act III of Our Town accomplishes.
It's not uncommon to relate to characters in a play or to have shared some of their experiences--that's the very nature of drama, after all--but not every stage production with relevant characters and common experiences moves many in an audience to tears, as Our Town has often done. What is there specifically in the conclusion of that play that reaches people so deeply and personally?
Because the characters are so real and everyone in the audience has experienced the same events and emotions as the characters on stage. By watching the characters on stage deal with these things, it takes the audience members along with them to relive their own personal events. It is a natural reaction. That's why the play is called "Our Town"--it is relative to the characters on stage and to every person in the audience.
Because what the audience experiences from watching Act III no doubt transports members back into their previous years and think about the same situation that occurred to them. That is what makes this so appealing. They are the experiences of the common person, rather than some royal lord or king.