Is the entire season of a drama worked out before it begins shooting?

Is the entire season of a drama worked out before it begins shooting?

Some TV shows work out the entire season and some don't. Most serials have at least some kind of map, and sometimes a show runner takes the entire staff to camp for a week or two before the staff assembles to start writing the new season. During that week of retreat, they think broadly of where they want their series to go and the kind of very large arcs the characters may have. There are other shows where that's irrelevant. With the CSIs, for example, it wouldn't matter because each episode is free standing, so they don't do that.