The wind is about to change in 1910 London! Bert, a man of many trades, acquaints us to the troubled Banks family of No. 17 Cherry Tree Lane. The children, Jane and Michael, have driven off yet another nanny with their naughty behavior; their father George is absent in their lives and demands order and precision from his wife Winifred who feels inferior in her role as a wife and mother.

Mary Poppins suddenly appears on their doorstep as a new nanny at just the right moment. Confident and decisive, she knows she must use common sense and a bit of magic to teach this family to value each other again. Mary Poppins takes the children on a walk to the park where they meet Bert who encourages them to see the magic that Mary can add to everyday life.

As Mary Poppins begins to win over Jane and Michael, Winifred continues to feel she is a disappointment to her husband. Little by little, Mary Poppins begins to help her also see the joy in life.

Helping George Banks is still a challenge. He faces pressure in his job as a banker and, because of a business decision, is placed on suspension with no pay. He struggles to find a way to connect to his wife and children. They, in turn, react with anger and frustration towards each other. Mary Poppins realizes this family is not yet ready for the lessons she has to teach them and leaves for a while.

Winter comes, as does a new nanny: Miss Andrew, George’s harsh and unpleasant nanny from his childhood, but Mary Poppins reappears just in time and surprises everyone with her return. The children are thrilled to see her and are soon magically whisked up the chimney where they meet Bert and his fellow chimney sweeps. They dance across the rooftops and eventually end up back in the Banks home. Shaking hands with the chimney sweep brings good luck, and all the chimney sweeps shake hands with George as they exit his house.

Luck is not far behind as George meets with the bank’s board of directors and learns they are actually promoting him instead of firing him because of the results of the business decision he made. Winifred appears, and side-by-side they walk the streets of London, while Mary Poppins takes Jane and Michael on one last magical adventure into the night sky.