Candace enlists her friends Stacy and Jenny to help her bust her brothers, so they run trial busting events in the backyard to prep for the real thing. Meanwhile, Phineas and Ferb create an unlimited power supply to propel a group of cyclone-like vehicles known as "Spinning Tops of Doom." Over at Doofenshmirtz Evil Inc., a new replacement robot for Norm has been called into action but when struck by the surge of power going through Danville, the robot turns on Dr. Doofenshmirtz and makes him the target.