This is a story about a man named Mr. Popper, a house painter who lives with his family in Stillwater, USA.
Mr. Popper paints people's homes for part of the year, but then takes the rest of the time off, which he uses to read and learn about the North and South Poles.
One of his heroes is Admiral Drake, an explorer who conducts expeditions in the South Pole.
Mr. Popper writes him letters to tell him how much he likes his work.
One day, Mr. Popper receives a crate from Admiral Drake that contains a penguin.
He names the penguin Captain Cook and the rest of the family loves him, although Mrs. Popper is worried about how they are going to feed him as they are short on money.
Captain Cook explores the house and lives in the refrigerator.
However, he suddenly gets sick and so Mr. Popper panics.
After writing to a penguin expert, Mr. Popper receives another crate and discovers a second penguin, Greta.
Soon, Captain Cook looks and feels better because he isn't lonely.
