The Grinch (Benedict Cumberbatch) hatches a sneaky scheme with his trusted canine Max and his new pet reindeer Fred to ruin this year’s Christmas when the residents of Whoville plan to make their annual holiday three times bigger that year: steal all the Christmas gifts from Whoville's houses dressed as a fake Santa Claus. While the Grinch plots his plan, Cindy Lou Who (Cameron Seely) plans to seek out Santa Claus to thank him for helping her widowed mother (Rashida Jones) every Christmas, but little does she know she is trying to blow the Grinch's cover.