The term "opening sequence" refers to the initial set of scenes or shots that are shown at the beginning of a movie, television show, play, or other form of entertainment. This is typically used to establish the setting, introduce characters and their relationships, provide background information on the storyline, and create anticipation for what's to come in the rest of the production. The opening sequence sets the tone and mood for the entire work, and can include visual effects, music or other audio elements, and dialogue or narration.