In the canon of talking cat films, there are a few greats that will not be topped: Garfield, Milo & Otis, Fritz the Cat.
In Grumpy Cat’s Worst Christmas Ever, she's voiced by the grumpiest of grumps, Aubrey Plaza. The Parks and Recreation star brings her stony temperament to the congenitally unhappy-looking Tard, who more than likely just wants snuggles and naps like any other cat. Her face, however, is the very picture of petulance.
Here's the first trailer.
Now, we wouldn't expect you to suspend your disbelief for a talking cat film, but this one — produced by Lifetime, no less — also asks you to believe that a 12-year-old girl would ask for a friend for Christmas (as opposed to a new iPhone and Silly Bandz or whatever it is these kids today are on about).
No matter, though, because any cynicism you might have about the thinness of the plot is effectively channeled through Plaza's irritated performance. Oh, and Tard's face, of course.