The unicorns are celebrating their favorite day of the year, complete with rainbows, cupcakes, butterflies, and all sorts of joyful things. But when it's revealed there's an impostor in their midst, the party comes to a screeching halt...

Will the unicorns welcome all and continue their fun in all its glittery glory? Unicorn Day delights in everything that's special: unicorns, celebrations, and most importantly, friendship.