Blackadder's Christmas Carol, on BBC One (UK)
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Caution: spoilers.

This is, of course, a parody of "A Christmas Carol", or more accurately, a reverse parody. It aired in 1988, between the third and fourth series of Blackadder. I saw it on my local public television station, though I don't remember if it was that year or sometime later. I don't believe it could have been later than the early 90s, though. Anyway, I watched it again in 2021, on Amazon.

In the Victorian era, Ebenezer Blackadder (Rowan Atkinson) is the most generous man in England, giving away all of what little he has whenever anyone asks. One year, the Spirit of Christmas (Robbie Coltrane) stops by just to say hello, but Ebenezer convinces him to show him his ancestors (from series 2 and 3), who gained rewards for being terrible people. Then he gets the spirit to show him his descendant from the far future, as he would be if Ebenezer turns bad, or if he turns good. All this, despite the spirit's best efforts, convinces Ebenezer to become a bad person. However, that ends up backfiring.

There. I've left out a ton of details, but I think I've said enough. It's all very much in keeping with the humor of the regular Blackadder series, which is to say hilarious.