I really love the 7-part TV series The Sympathizer on HBO. As wacky as it could be, it filled in some of the context from when I worked at a Vietnamese-owned clinic with a large number of Vietnamese patients. It still humbles me some of the adversity people have been through. Spoilers after the break.
I felt like it was fairly clear (to me) that the Blood Brothers were just one guy, Tyler Durden-style. The Captain didn’t have a name because he was Bon’s suave, Americanized alter ego. The Captain could ignore the grief of the dead wife and kid. It’s why Bon was so offended by the Captain sleeping with Sofia. The Captain could function when Bon couldn’t stand up. I’m pretty sure they never did anything of substance on screen at the same time.
Man? I’m not sure, but I think the Commandant was just a burned-up guy that Captain Bon was projecting Man’s face onto. Cap’s awfully good at projecting RDJ everywhere.
It ended with the Captain joining the other ghosts as Bon let himself move on a bit, no longer pretending to be a spy.