Eifersucht (1925)

A couple are at the theatre with a playwright friend. At the end of the play the jealous husband strangles his wife to death. When the play ends, the man talks to his friend about such a nonsensical finale, telling the author that no man with any sense ever gets jealous enough to choke his wife in these modern times. The playwright decides to test this supposedly perfect couple about their happy feelings for each other.