During a post-screening Q&A after the New York Film Festival Premiere, Ethan explained that they weren't consciously thinking about about the themes of mortality until they were writing the final segment, "The Mortal Remains," the last one to be written before filming. (The first was composed 25 years ago. They're just two morbid dudes.)
"We thought: This character dies in this story, that one dies in that story," the director said. "Maybe in this one they are all dead?"
"The Mortal Remains" strays from the straightforward parable format of the other entries, and though it's not the only part of Buster Scruggs to deal in fantasy, it's the most elusive. It begins with an unlikely group of travelers in a stagecoach: A pious, snotty woman (Tyne Daly); a libidinous trapper (Chelcie Ross); and a gambling Frenchman (Saul Rubinek). Facing them are a dapper Irishman (Brendan Gleeson) and Englishman (Jonjo O'Neill). As the passengers share their histories on the way to a place known as Fort Morgan, their conversation becomes about the nature of humanity. As the sun sets, the coach is shrouded in an ominous dark blue that brings with it an unmistakable sense of dread.
Eventually, the Irishman and the Englishman reveal their mission: They're "reapers" or "harvesters of souls." The passengers take this to mean "bounty hunters," but clearly their duty is more metaphysical than that. The coachman, shrouded in black, doesn't stop -- that is, until he gets to their lodging for the night. It's at a midpoint; purgatory, if you will.
The eternal chilliness of that ending pairs curiously with the first installment, where the cocky Buster meets his end at the hands of an upstart sharpshooter and gains literal angel wings, singing his way to heaven. (Another parallel between those two: A Frenchman. There's a similar looking one played by David Krumholtz at the saloon card table with Buster, and the Coens reportedly said in a Q&A they wanted to cast the same actor for both parts.) Ultimately, The Ballad of Buster Scruggs delivers no overarching theory about what happens when we die, but it's certain that we all do, and it often ain't pretty.
Sure, it's something of a cop-out to argue that vague agnosticism is the film's guiding principle, but it is difficult to discuss Buster Scruggs in concise fashion. All the bits have merits, and most have some nagging flaws -- the presence of James Franco is unfortunate, for instance. But while you may be tempted to jump ahead or skip around, the way you might for a season of, say, Black Mirror, don't. Let the Coens take you on funny, yet incredibly depressing, journey through a vicious land.