"Jollybells" is a Christmas-themed episode that premiered on December 2, 2014 with "Gingersnaps and Grumpy Snaps" on Disney XD. It was revealed by series storyboard artist Douglas McCarthy who also posted several of his storyboard panels from "Jollybells" on his blog.
It is the thirty-sixth episode in the series.
Happy must figure out a plan to bring the holiday spirit back to the villagers of Jollywood after the Glooms drain the joy out of the town using a magical Joybuster device.
Jollywood is celebrating Jolly Day at the village center with a huge Jollywood Tree, while the Glooms have their version of the holiday called Gloomy Day. Grim presents Hildy with a gift: a machine called the Joybuster, designed to drain the joy out of people. To test the machine, they use it on a group of carolers from the village arrived at their front door, and the machine sucks the joy out of them, literally turning them blue and depressing. The Glooms then go the village to make sure that one in Jollywood will be joyous.
Grim and Hildy appear at the Jolly Day events, which are hosted by Queen Delightful. They then target Doc, Grumpy, Sleepy, and Sneezy, and the other villagers, turning them blue. Happy notice his friends' depressing behavior, and tries to keep their spirits up. Later, the Glooms suck the joy out of Dopey, Lord Starchbottom, and Delightful, which is difficult because apparently she has a lot of happiness. Bashful, who hasn't been targeted yet, and Happy then found out it's the doing of the Glooms, and they set up a plan to return the villagers' joy.
Their first plan is to trick the Glooms into believing that they have all of the joy by using the Joybuster on two makeshift Bashful and Happy mannequins next to a table, with the real dwarfs giving out voices underneath them. The next plan involves Happy singing in an attempt to uplift The 7D's dull spirits at the cottage and then lead them and the villagers to the huge Jollywood Tree. Hildy can't believe that she was fooled, and the Glooms go back to use the Joybuster on Happy. But this is even more difficult than Delightful's -- Happy's joy is so big that it overloads the machine, causing it to explode, and all the joy cascades over the sky, returning it to everyone. As everybody gathers around the tree feeling happy again, even Grim and Hildy find joy inside themselves—though Hildy finds it gross. The episode end by Happy saying "Happy Jolly Day!".