Futurama is displaying correctly in Plex for me, as well as my other TV Shows including those that have new episodes, or that I add new episodes to it.
You can always go to thetvdb.com and search for the show, in this case Futurama, and you get results, TVDB is not down or having issues. If you get a delay or no results, TVDB may be having issues.
Also, make sure you follow the naming scheme that Plex prefers : support.plex.tv/hc/en-us/articles/200220687-Naming-Series-Season-Based-TV-Shows
If your filenames aren’t in this manner, you can search for, and use, Filebot to rename the files as it can search TVDB and rename your files in bulk.
Have you tried the Plex dance? I think some of you have. I think it’s move your Futurama, or TV show, directory out of your Plex library directory (don’t delete the directory), Scan your TV Shows, Optimize database, Clean Bundles, Empty Trash. Move Futurama back into your Plex Library directory, Scan, Optimize, Clean and Empty.
As an example:
Futurama/Season 01/Futurama - S01E01 - Space Pilot 3000.mkv
Futurama/Season 01/Futurama - S01E02 - The Series Has Landed.mkv
Futurama/Season 01/Futurama - S01E03 - I, Roommate.mkv
You may try Refresh Metadata under the ‘…’ of the show or library. WARNING!!! IF YOU CHOOSE ‘LIBRARIES’ or your TV Shows library, it WILL take time depending on the size of your library(ies) as Plex will try to refresh the metadata of each and every item, movie, song, episode, etc. so be careful of the depth of which you choose to refresh the metadata. 
