Plex Documentation → Your Media → Naming & Organizing TV Shows
Make sure you follow Plex’s organization and naming requirements.
Plex Dance the entire show after renaming, reorganizing. For Star Trek, as you’ve multiple shows from the franchise, move them all out of the Plex library, perform steps 2 - 4, rename the shows, then return them one at a time to the library, waiting for Plex to complete processing each show before adding the next.
Use the show names as listed in TheTVDB.com. Adding the year helps. Leave out any special characters that are invalid in file names (:, etc). Adding the TVDB/TMDB ID is optional, but helps with matching.
/TV Shows <-- TV Show library points here
/Star Trek (1966) {tvdb-77526}
/Season 01 <-- "Season" in English. Two digits for number, unless four needed.
/Star Trek (1966) - s01e01.ext <-- sXXeYY mandatory; ext = mkv/mp4/etc
/Star Trek The Next Generation (1987)
/Season 01
/Star Trek The Next Generation (1987) - s01e01.ext
If you wish to keep the franchise/genre subfolders, you’ll have to modify things a bit
You can have individual libraries for each genre/franchise/etc.
You can have a library for all shows, but you must add each subfolder to the library, not the /TV Shows main directory.
/TV Shows <-- No TV Library points here
/Drama
/Humor
/Star Trek
/Everything Else <-- Uncategorized shows go here