For example, the most famous is the murder in the secret room.
Blizzard Villa should be classified as a secret room murder, but it is often an upgraded version of the secret room murder, because this mode is often a serial murder.
Villa in a snowstorm is often closed.
Advantages of closed killing relative to the scene: First, the police can't intervene.
Second, don't worry that the other party will run away. .
Third, it can oppress each other's psychology and make them fear.