Claymation Christmas Celebration, on CBS
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Note: Most websites call this "A Claymation Christmas Celebration," but the word "A" isn't actually in the title. (I have no idea where anyone got the "A" from, so I'm not using it.) In fact, the proper title is "Will Vinton's Claymation Christmas Celebration." (But I generally like to drop the creator's name from things that include their name in the title. Though I admit it does sound better with either "A" or "Will Vinton's" in front of the title. Oh well.) Anyway, whatever you call it, the special first aired in 1987, and I'm sure I watched it at the time. Then it fell into obscurity. Finally, in 2015, I got it on DVD (which also includes Easter and Halloween specials).

So, it's hosted by two claymation dinosaurs, Rex and Herb. They introduce a series of segments featuring different Christmas carols. Rex tries to give some history of each carol, but Herb is constantly distracted by other things, like snacks. Meanwhile, Rex is constantly interrupted by various other creatures singing the wrong lyrics to "Here We Come a-Wassailing," which really bugs him (though Herb seems to enjoy it). And that running gag is what I mainly remembered from the first time I saw the special (when I was twelve). And I guess I must have also remembered that one of the carols was performed by the California Raisins, though I had no memory of what carol they actually sang. (It was "Rudolph the Red-Nosed Reindeer.") In fact I didn't remember any of the specific carols from the special. But anyway, it was fun to see it again, and I'm glad to own it. The songs are decent, the interstitial bits with Rex and Herb are amusing, and the whole thing is just enjoyably offbeat. And I don't know what else to tell you....