In a comical bungle, Curious George accidentally gets swapped with an identical-looking Royal Monkey from a small kingdom. George believes he is visiting his dream theme park, Castleland, and cavorts in the somber kingdom. The stuffy Royal Monkey believes he is staying with Ted until it's convenient to return home. Before being un-swapped, George brings some chaos but mostly joy back to the kingdom, its princess, and her father the king. And Ted teaches the Royal Monkey to be more carefree.
—Universal