Duplicate unrelated files turning up

[tom80H]

What folder is this tv show library of yours linked to?
From the screenshot… it should be

/Volumes/Thunderbolt Backup/Videos/English videos/TV/Science & Nature/

However I suppose you’re pointing it to

/Volumes/Thunderbolt Backup/Videos/English videos/TV/

Plex doesn’t like it if you deviate the folder structure from the naming schema.

Library Folder   <- the folder linked to your library...
  TV Show
    Season XX
      TV Show - sXXeYY - optional episode name.ext

Where XX is the 2-digit season number and YY is the 2-digit episode number. Library Folder could be pretty much any name – you can also add multiple library level folders to a single Plex library… however there should be no additional folder levels between that folder(s) and the tv-show folders!

Edit:
After fixing this, you might need to perform a Plex Dance to ensure Plex fully re-scans the episodes:

The Plex Dance ™

The purpose of this is to remove all cached metadata and xml data for an item that Plex usually keeps. This helps when you want to “start from scratch” for particular item move all files for the media item out of the directory your Library is looking at, so Plex will not “see” it anymore scan the library library (to detect changes) empty trash clean bundles (in menu next to server name, when accessed under ‘More’) double check naming schema and move files back scan the library Support articl…