The game's each, individual seven levels are based on an episode of the television series.[3] The first stage of the game consists of Phineas and Ferb beginning their plans to destroy and construct a giant roller coaster. Phineas primarily is the one in his duo to actually find and gather the tools and objects necessary for it, while Ferb primarily is used to actually utilize each device. The two need to avoid their sister, Candace, as she is persistent in her desire to bust them and get them in trouble with their mom. Once every part in the needed list is found, the two construct the devices in the form of little puzzles which end with the creation of roller coaster tracks and engines. Once everything has been completed, the two race in the roller coaster down the tracks to compete. Throughout their way, they as well build other devices, from a water slide to a winter wonderland, and occasionally bump into the neighborhood bully, Buford.[1][3] After constructing all 5 rides in the game, Candace prepares her ultimate busting attack, after which Phineas remarks "Hey, where's Perry?" You suddenly find yourself playing as Perry the Platypus fighting in Doofenshmirtz Evil Inc, the player using the Touch Screen to help Perry fight Doof. After Perry's final attack, the resulting explosion obliterates all the rides Phineas and Ferb have made throughout the game, right as Candace drags her Mom into the backyard. Phineas and Ferb, not knowing what just happened, build a time machine and send themselves back to before the rides were destroyed.