how to remove episodes that were added via missing episode fetcher?

[Bladefin]

I made a mistake and had missing episodes selected,I managed to do a refresh it worked but then I noticed I had the missing episodes on another series,I couldn't get rid of them so I had to move them out of the folder location and did a refresh and then put them back,a total nightmare but that was the only way, I won't be making that mistake again.