I really enjoyed this episode. So many of the shows in this series are based on fundamental greed. This one is really fun. I like the protagonist. He has suffered long because of a marriage made in hell. This has caused him to trust people to compensate for his unhappiness. We see him as a poor sucker who just can't catch a break. Finally he acts. Granted, it is the ultimate crime, but we know how far he was driven. The nice thing about this episode is that we are really kept in the dark all the way. We trust the "nice" people, but these are Hitchcock stories.
Incidentally, I've decided to ignore Hitchcock's little moments at the conclusion of the show where he tells us that the characters who managed to escape were ultimately punished. I wonder if this was a code thing or a literal commitment to "crime does not pay." If taken as gospel, it ruins many episodes.