A spin-off (also spelled spinoff) is derived from already existing works that focus on more details and different aspects from the original work (e.g. particular topics, characters or events), and includes books, comics,
radio programs,
television programs, animations, films,
video games, or any narrative work in any medium. In
genre fiction, the term parallels its usage in television; it is usually meant to indicate a substantial change in narrative viewpoint and activity from that (previous)
storyline based on the activities of the series' principal protagonist, and so is a shift to that action and overall narrative thread of some other protagonist, which now becomes the central or main thread (storyline) of the new subseries. The new
protagonist generally appears first as a minor or
supporting character in the main storyline within a given milieu and it is very common for the previous protagonist to have a supporting or cameo role, at the least as a historical mention, in the new subseries. Spin-offs sometimes generate their own spin-offs, leaving the new show in its own series only vaguely connected to the original series; for example, the
police procedural franchises of
NCIS/
JAG and
CSI have both spun off multiple shows, including multiple spin-offs from series and spin-offs from spin-offs. ==Types and variations==