Yeah, I guess I'm being a bit nit-picky about the plot. Despite making the connection between the father's absence and the locked door, I honestly did very much enjoy listening to the show. It was wonderfully moody, and the acting and production values were terrific. AND, as E.G. Marshall points out, it's more than a mystery; it's about honor. I imagine that in England at the time the story was written, the theme of honor had quite a bit more resonance. Here's a rich, respected guy who would rather be locked up in a sealed room and croak himself than be dishonored, abandoning a wife he KNOWS is dying as well as causing his poor son to become orphaned and, eventually, quite neurotic. Looking at the story from that perspective, the black door becomes quite a tidy little metaphor regarding the repressive nature of English society in Sir Arthur's day. That's pretty brilliant. (Now I've really gotta read that story!)