A boy name Phineas meets an alien named Meap, who warns him of an impending danger that only he can stop. Phineas embarks on a journey around the world and meets the beautiful Isabella in New York, the studious Baljeet in India, and the hot-headed Buford in Canada. Together they must collect the Eight Tunes and stop the plot of Phineas' snobby neighbor Thaddeus from awakening a beast capable of causing the end of the world.