Phineas and Ferb need money to pay off the dept they owe the companies that they order supplies from. Dirty Matt advises them to borrow money from his friend who is a loan shark, but when they do, they owe him interest and now must raise money to avoid getting hurt. Meanwhile, Dr. Doofenshmirtz, tired of his clothes, nose and fingers getting caught in closing doors, tries to eliminate all doors in the tri-state area.