Configure the agent back to TheTVDB. You’ll need that, as you’ll need the DVD ordering.
Then, name your S01E01 files as:
Show Name - S01E01 - part1.ext
Show Name - S01E01 - part2.ext
Then, edit the show itself, and in its advanced settings, configure it to use DVD ordering. Then, refresh metadata for the show. You may need to Plex Dance those files.
This should result in the ordering you want.
I’d recommend combining those episode 1 and 2 files to simplify things though.
Ultimately, I’d recommend changing your library over to the new Plex TV Series agent and scanner though. I’m not sure the legacy TVDB/TMDB agent will see much development going forward. When you do change the library over to the new agent and scanner, you can still choose the ordering for individual series, it’s just named a little differently.
[Edit]
I mis-read the original description; “aired” order is what is needed if episode 3 should be “Heart of Darkness.” I also mis-read the part about the file already being combined.
Takeaway: Reading is fundamental.
