Parks and Recreation's Aubrey Plaza is the voice of Grumpy Cat. That's right, the girl who plays the notoriously grumpy April Ludgate is about to play the notoriously grumpy-faced, stubby-legged cat in Lifetime's upcoming movie, Grumpy Cat's Worst Christmas Ever. I know, it's a lot to take in at one time. The live-action movie will revolve around an overlooked pet store cat and the little girl who can communicate with him. Essentially, let's just be prepared for cameos from other Internet memes, and a lot of this.