The film is set in 1930s depression-era London (the time period of the original novels) and is drawn from the wealth of material in PL Travers’ additional seven books. In the story, Michael (Whishaw) and Jane (Mortimer) are now grown up, with Michael, his three children and their housekeeper, Ellen (Walters), living on Cherry Tree Lane. After Michael suffers a personal loss, the enigmatic nanny Mary Poppins (Blunt) re-enters the lives of the Banks family, and, along with the optimistic street lamplighter Jack (Miranda), uses her unique magical skills to help the family rediscover the joy and wonder missing in their lives. Mary Poppins also introduces the children to a new assortment of colorful and whimsical characters, including her eccentric cousin, Topsy (Streep).
Each year at Christmas they disrupt his tranquil solitude with their increasingly bigger, brighter and louder celebrations. When the Whos declare they are going to make Christmas three times bigger this year, the Grinch realizes there is only one way for him to gain some peace and quiet: he must steal Christmas. To do so, he decides he will pose as Santa Claus on Christmas Eve, even going so far as to trap a lackadaisical misfit reindeer to pull his sleigh.
Meanwhile, down in Who-ville, Cindy-Lou Who—a young girl overflowing with holiday cheer—plots with her gang of friends to trap Santa Claus as he makes his Christmas Eve rounds so that she can thank him for help for her overworked single mother. As Christmas approaches, however, her good-natured scheme threatens to collide with the Grinch’s more nefarious one. Will Cindy-Lou achieve her goal of finally meeting Santa Claus? Will the Grinch succeed in silencing the Whos’ holiday cheer once and for all?