1. A Lead In is a mini story which occurs before the main plot. It is used to warm up the audience and set up the events which lead to the main story. Aside from being a catalyst, it usually has very little relevance to the rest of the episode. It may also be used to stretch the script to a sufficient length. A Lead In differs from The Teaser in that: * It does not occur before the credits (and is therefore not intended to grab the audience before a channel change). * The Teaser does not have to be a separate set up, it can be an intrinsic part of the main plot.