The War with Grandpa is a 2020 American family comedy film directed by Tim Hill, from a screenplay by Tom J. Astle and Matt Ember, based upon the novel of the same name by Robert Kimmel Smith. It stars Robert De Niro and Oakes Fegley, along with Uma Thurman, Rob Riggle, Laura Marano, Cheech Marin, Jane Seymour, and Christopher Walken. The film is about a young boy who works to get his grandfather to move out of his room after he moves in with his family.
Peter and his grandpa used to be very close, but when Grandpa Jack moves in with the family, Peter is forced to give up his most prized possession: his bedroom. Peter will stop at nothing to get his room back, scheming with friends to devise a series of pranks to drive him out. However, grandpa doesn't give up easily, and it turns into an all-out war between the two.
