1. It is characterized by a humour with a sexy, erotic touch. In that clip, this touch is emphasized by the woman showing her legs and underwear. Alfred's exagerrated mannerisms reveal much of the theatricality that is a trademark in the actors from early movie musicals.
2. Two moments attracted my attention: first, when they are talking to each other, the muffled sound indicates that their voices are coming from inside the bedroom; and second, the gun sound, which is absolutely fake, and that's the reason why the scene is so fun, because the husband really believes his wife is dead.