Hearths Warming Eve has come once again in Equestria and all around, every pony is in a most merry of moods. Well...maybe not every pony. Sickened by the sickly sweet feelings of the holiday, Cozy Glow attempts to ruin the occasion by stealing the magical television from Twilight Sparkle to cause mass chaos. However, a magical surge sends herself through the portal and it is up to the Mane Six, Spike, and Starlight Glimmer to go after her and stop her from causing more destruction. This lands them in the small town of Whoville, where the citizens are readying themselves for Christmas time. But all is not as joyous and merry as is to be believed when the Christmas hating Grinch seeks to steal the very holiday itself.

Will our heroes be able to stop Cozy Glow and help the Grinch learn to love Christmas? Or are some hearts just two sizes too small to learn to love?