Crash and Cortex sneak into the Academy through the sewer system, where they fend off an attack from Dingodile. After Cortex finds Nina and has an encounter with Madame Amberly, he recalls the origin of the Evil Twins; when Cortex was an 8-year-old student in the Academy, he used his two pet parrots Victor and Moritz as test subjects for a prototype of his Evolvo-Ray, but the experiment resulted in the parrots being transported to the Tenth Dimension, where they would be mutated by the environment's severe "reverso-radioactivity". The trio return to the Iceberg Lair, repair the Psychetron and travel to the Tenth Dimension to face the Evil Twins. Upon their arrival, Nina is kidnapped by an evil doppelganger of Crash and taken to his desolate home on Twinsanity Island. After cornering Evil Crash, Cortex valiantly offers himself in Nina's stead, which leads to a chase. Crash, Cortex and Nina escape Evil Crash and make their way to the Evil Twins' compound, where Cortex confronts the Evil Twins and commands them back into their cage. The Evil Twins transform their cage into a giant robot and engage in a final battle with the trio. The Evil Twins are defeated and flee the compound, only to be devoured by Evil Crash when they take refuge in his home. After the trio return to their own dimension, Cortex attempts to eliminate Crash, but the malfunctioning Psychetron teleports Cortex into Crash's mind, where he is trapped with a crowd of dancing Crash duplicates.