Green screen is commonly used in TV dramas to create realistic scenes in a cost effective manner. The document describes 4 shots where green screen is used: 1) A cruise ship crash scene to avoid the costs of creating an actual crash. 2) An arctic scene to avoid traveling to the location. 3) A street scene to represent houses on a hilly road without finding the perfect location. 4) A street scene with falling snow to extend the setting in post-production. Green screen allows complex scenes to be filmed efficiently and within budget constraints.