Board Thread:The Panopticon/@comment-1293767-20151029072618/@comment-5918438-20161207045040

Four rules of the multi-parter
Two or more TV episodes are considered a two- or multi-parter if the following statements are found to be true:

Finer detail

 * Rule 1: The episodes follow each other directly in broadcast, within a consecutive run.
 * - Specials, such as those aired on Christmas, are not usually included in a consecutive run, as standalone specials, with the one exception being The End of Time.
 * - ''When a series is divided into two distinct runs, as with series 6 and series 7, those runs are to be considered separately.
 * - It is not required that the length of time between episodes is 1 week, though this is usually the case.
 * Rule 2: The episodes belong to the same production block, with the same director in charge of all of them.
 * Rule 3: A minimum of one (1) linking character is present in all episodes. A linking character may not be present in a majority of episodes (50%+) in that series run, and those only appearing at the end (last 10% of episode) do not count.
 * Rule 4: If a story was broadcast as a serial, it can have different directors or lack a linking character in some episodes without affecting its serial status. Recording blocks are ignored for Hartnell serials. These rules really apply to those stories which are not serialised.