In Grampa in Oz, Dorothy's Grampa, a kindly former soldier, finds himself unexpectedly swept away from the struggling kingdom of Ragbad along with its young Prince Tatters by a giant magical flower. Landing in the strange land of Perhaps, they team up with Bill, an animated weather vane rooster, and embark on a whimsical and perilous journey. Facing challenges like indecisive Maybe people and pursuing villains who want Tatters' throne, the unlikely trio must rely on courage, quick thinking, and newfound friendship to navigate bizarre landscapes and ultimately find their way to the safety and wonder of the Emerald City, where Grampa hopes to reunite with Dorothy and Tatters seeks Ozma's aid.