Speculating on the nature of the afterlife is one of those magical abilities afforded by film, and has long been a subject of films that sought to find the core of existentialism.
Considering how religion and spirituality permeate our culture, it's no wonder that film has long been used as an effective medium for portraying all our conjectures about life after death.
In the first half of the 20th Century, directors like Ingmar Bergman had already begun to explore what film could contribute on the topic of existence and its unique ability to hypothesize about the afterlife realistically.
The genius of film is that it allows us to suspend this disbelief easily, especially under the guise of a post-life film that inherently deals with all the issues we suspect might be a factor once we die, but never go to the trouble of inhabiting, until films do it for us!
Films that deal in topics this deep are often overlooked, because at their essence films are supposed to be an escape from these ideas, but sometimes, a film like this makes us confront topics the importance of which we never truly understood.