The Trolls and the Christmas Express

The Trolls and the Christmas Express is a 1981 animated Christmas television special produced by the Canadian-based Atkinson Film-Arts for Pooled Film Services.

Plot
Six troublesome trolls, whose leader is called Troglo (voiced by Hans Conried), use their mischievous magic to sabotage Christmas by infiltrating Santa's village disguised as elves. After a week of wreaking havoc but still not completely ruining Christmas, the trolls get a devilishly clever idea: on the day before Christmas Eve, they get the reindeer dancing and singing all night long. The next day, the reindeer are so tired that they cannot find the energy to pull Santa's sleigh. Although it is likely that Christmas is ruined, the elves quickly devise a plan to link the train from Santa's village with tracks that travel all over the world so that Santa can deliver the toys by using the Christmas Express.