No pun intended - we start off with quite the powerful scene ... we get to see someone who is able to "mail" something ... but without a stamp and any real address ... which is the starting off point to get into what happens with mail that has .... well issues and couldn't be delivered.
We get to see the day to day live and routine of someone who does the job ... and does it well. But he is just one player ... because we also get to see the person who did the "mailing" ... before he had the issues that made him .... well that got him trapped (not really through his own fault).
What is kind of funny, the movie does suggest towards the end, that we saw something that actually happened ... showing what happened to the "real" people of the movie or how they got into the situation they got in ... but at the very end of the credits it does tell us that it is a work of fiction ... but well done and had me for a minute.
Really well acted and really interesting structure ... it was missing something ... a last piece to kick this over the top for me, but it still is amazing to say the least ... if you are into weird movies.