Upset that he has to share the room he loves with his grandfather, Peter decides to declare war in an attempt to get it back.

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.