Are we counting war films where the enemy kills himself rather than facing dishonor?
In Spider-Man #34, v. 1, Kraven the Hunter admitted he had impersonated Spider-Man in order to make him look like a criminal.
“Deal with the devil” stories often have the devil keeping his word: “The Devil Went Down to Georgia,” “Dealer’s Choice” (the devil tries to cheat, but once he loses, he honors his word – and gets beer and food for the others).
The obvious example is the bridge scene in Monty Python and the Holy Grail.
Anyone not answering “these questions 3” correctly flies off the bridge into the abyss.
When Arthur crosses the bridge and is asked about the airspeed velocity of an unladen swallow, he asks for clarification.
“What do you mean, an African or European swallow?”
The bridge-keeper doesn’t know, so he himself goes flying off into the abyss.
I’m trying to remember the name of the Christie novel . . . (Googled: Crooked House).
It turns out a child is the multiple murderer. At the end, an elderly relative drives off a cliff with the child in the car. She saw herself as a suitable sacrifice in order to deal with the problem quickly and permanently.