After the unvailing of Phineas and Ferb's Brain Switching Machine, Candace comes up with a plan. She and Stacy sneek into Phineas and Ferb's room while they are sleeping and use the machine to steal Phineas' confidence for Candace. The next day, Phineas has become stressed out. While Candace loses her highstrung attitude, and becomes popular among the neighborhood teens. Phineas, Ferb, Isabella and the Fireside Girls try to use the Brain Switching Machine to get Phineas' confidence back, but Candace thwarts the kids' every attempt. Eventually, the machine breaks. Realizing Candace is invincible with Phineas' confidence, Phineas considers giving up. Isabella reminds Phineas that he would never let a brain draining machine slow him down. Suddenly, Phineas' inner confidence emerges, the kids realize that the machine never took away Phineas' confidence, he had it all along. The expierience gives Phineas a plan, if Phineas never lost his confidence, Candace never had it. Phineas and the kids show up in front of Candace's crowd riding a rollercoaster, all the teens go to ride in it and drag Candace with them. Candace, realizing her plan failed, loses her confidence and panics on the rollercoaster. All the teens are disgusted at Candace stressing out and walk away.