Ebeneezer Scrooge (Played by, obviously, Scrooge McDuck) is a cold hearted miser, who hates Christmas, and is only concerned with greed, and even overworks his employee Bob Cratchit (Mickey Mouse). However, his life begins to change when he is given a warning by the ghost of his old partner Jacob Marley (Goofy) that he'll be visited by three ghosts, which show him his once happy past, the present with Cratchit's ailing son Tiny Tim, and the grim future that Scrooge will face if he doesn't change his ways.
So, in essence, it doesn't really deviate too much from the Dickens plot. But I'm kind of glad they don't, because the story flows and moves so well that it really doesn't need to ever be more than a retelling of a classic tale. The animation is great, with some really nice visuals, and beautiful art. It holds up wonderfully 30 years later.
On the voice acting standpoint, as is the norm with Disney, it's top notch. The most notable voice actor being Alan Young as Scrooge. This would be the first time Young voiced the character, and certainly would not be his last, as only a few years later, Disney would give us the timeless classic known as Ducktales. All the other characters sounds great too. Though Goofy as Marley does sound weird, though that has to do with me being more used to Bill Farmer. Hal Smith does a fine job, it just doesn't feel as Goofy as what Farmer would bring later on.
Overall, this is my favorite Christmas special of all time, and easily my favorite adaptation of the classic Dickens tale. It can be funny, it can be sad, it can be dark, and it does all these well. It's a pitch perfect retelling of the tale, and one of Disney's finest works. If you haven't checked it out, I highly recommend it.