Episodes that are 95% flashbacks and aren't even fillers... >_>
edit: 5 in a row so far... -__-"
edit: 6....
Sounds like you're watching Naruto, Dragonballs, or Bleach.
Naruto Shippūdden.
I actually don't recall that ever happening in Dragon Ball Z or Bleach. I don't even remember any fillers in DBZ. Bleach had the worst fillers of all time... Right in the middle of Hueco Mundo they're just suddenly teleported to the future where everything's over and they're just casually screwing around for a season... like what the hell... and then it happened several times after that too.
DBZ would just show what was going on somewhere else (I assume it could have been filler), but it was done more of a Game of Thrones sort of way than seeming like a filler. Like, you were kept in the loop with everyone's stories so it wasn't like a filler.
But yeah, Naruto is god-awful with fillers. I'm on 224 right now of Shippūden. It's a filler season. I'll probably just skip right on over to 242. I actually watched the first like 3 minutes of each episode of the previous filler arc since it had some seemingly non-filler at the start of each one. This one seems like it'll be all filler though. They did at least transition into it nicely, it doesn't feel out of place or anything.