The One and Only Ivan is a 2012 novel written by Katherine Applegate and illustrated by Patricia Castelao. Based on the true story of a silverback gorilla who spent 27 years living in a mall in Washington state, the novel is written from the point of view of Ivan, a silverback gorilla who lives in an enclosure at a mall. In 2013, it was named the winner of the Newbery Medal. The novel was adapted into a Disney+ film in 2020, and has been followed by three sequels: The One and Only Bob (2020), The One and Only Ruby (2023), and The One and Only Family (2024).