Ruiko uses the Level Upper on herself and her friends, becoming happy just to have an ability of her own. Meanwhile, Kuroko takes care of more Level Upper offenders and gains more injuries in the process, keeping them a secret from Mikoto. Remembering when they ate shaved ice the other day, Mikoto and Kuroko come to the conclusion that the Level Upper is using synesthesia to manipulate multiple senses with just audio. Just then, Kazari hears from Ruiko that her friends have suddenly fallen unconscious due to the Level Upper, later arriving at her apartment to find her unconscious too. After Ruiko is admitted into hospital, Mikoto feels guilty, believing she hurt Ruiko's feelings by saying levels didn't matter, and asks to co-operate with Judgment in finding the culprit. After learning from the frog-faced doctor, Heaven Canceller, that the Level Upper victims seem to share a brainwave pattern with someone, Mikoto and the others discover the culprit is Harumi, who had been using the Level Upper to connect the thoughts of espers like a network. Kazari, who had visited Harumi earlier and discovered her notes on synesthesia, is taken hostage by her. Noticing Kuroko's injuries, Mikoto goes by herself to rescue Kazari and stop Harumi.