A sequel to Phineas Flynn in Around the World in 80 Days
After Phineas pulls a prank on the local bully Buford, their fight causes them and Phineas' friends to stumble into a hole leading to the center of the earth. Phineas and Buford must set their differences aside to survive the dangers below the earth's surface.
Phineas- A reckless yet caring 10 year old boy.
Irving- Phineas' lovable yet clumsy freind and sidekick.
Isabella- Phineas' girlfriend he met in India, she has been adopted by Phineas' family.
Buford- The neighborhood bully and Phineas' rival, he has a crush on Isabella, but she is positively repulsed by him.