Grumpy Cat is a lonely cat living in a mall pet shop. Because she always gets passed over and never gets chosen by customers, this kitty develops a sour outlook on life until...one day during the holidays, a very special 12-year-old girl named Chyrstal enters the pet store and falls in love with Grumpy Cat. A unique friendship is formed between the two when Chyrstal finds she is the only person who can hear this unique feline talk. Will Grumpy Cat learn the true meaning of Christmas, or will it be in Grumpy's words, "Worst. Christmas. Ever?"