Writing for TV ain't easy-- coming up with fresh plots on a weekly basis can be tough. Fortunately for writers, most shows follow the same basic format week-to-week, so they don't have to come up with radically different plots every seven days. One of the most popular show types is the "Of The Week" format, in which a core cast of Regular Characters deals with a new problem every week. This combines the stability of a template show with the possibility of new, exciting stories. In script terms, the One-Shot Character who comes in with a problem and disappears after is called a client.