MechaBot and Amato play a video game, and the robot criticises Amato's competence because they keep losing. Amato's mother asks from downstairs why he isn't sleeping since he has an exam tomorrow. He prepares for late night studying, but before he gets to do so, loud, terrible singing begins outside, disturbing him. The next morning, he falls asleep in the exam, only getting 5 minutes to do it. Amato's friends ask what's wrong, and he says he couldn't sleep due to the racket that lasted the whole night. Despite Mara's advice to study earlier, Amato insists that he studies best at night. Unfortunately, the noise is even worse with louder music, and Amato only gets to write his name and date in the next exam.
On the evening before the third test, Amato forces MechaBot awake and drags him outside, where they find a robot singing in the playground. MechaBot recognises him as Karok, but notes that his voice wasn't as bad compared to when he last met him. In his excitement of gaining an audience, Karok sings on the merry-go-round, which amplifies his voice as it spins. Amato uses mechanized buckets to block the sound, but Karok knocks them off. MechaBot mechanizes a watering can over Amato's head to form the Mechaspeaker to counterattack Karok's singing, but Karok overpowers them and escapes, just before the sun rises.
This time, none of the class slept well due to the commotion, but Amato still struggles while his friends don't find the exam to be that hard. Rubika's information says Karok has a beautiful singing voice, which Amato disagrees with. Mara uses the other information on him - that he loves to sing and dance and can't resist a challenge - to stage a singing contest to bait Karok. Pian and Deep have an onstage rap battle while Amato plays a mechanized DJ. Karok jumps onstage and they set off a cage to trap him, but he dances his way out of it by breaking the roof with his feet.
Mechamato stops Karok from leaving by inviting him into a break-dance battle. The sky darkens from Karok's voice, so Mechamato uses the opportunity to equip extra stuff on himself during Karok's turn. He becomes a walking light-show by his next turn, during which a spotlight lands on Mara, who sings melodiously on how the red hero will always triumph. Karok is dumbstruck, reluctantly admitting defeat, but Pian hinders Amato from capturing him as he believes his voicebox is broken. That evening, Pian repairs it at the garage, but he gives Karok the wrong voicebox. Regardless, Karok is glad to sing normally, but Amato wastes no time to capture him once he starts singing again.
This episode provides examples of:
- Batman Gambit: Mara exploits Karok's inability to resist a challenge (plus his talent for singing and dancing) by arranging a singing concert to bait him. Pian and Deep rap-battle each other before Karok jumps onstage as a contender, and a cage is dropped on him. When Karok breaks free from it, Mechamato invites him to a Dance-Off to stop him from escaping.
- Cue the Sun: Karok's broken singing darkens the sky with thunderclouds during the Dance-Off, but after Mechamato (and Mara's singing) pulls off an astounding performance during his turn, the sky returns to being bright, as if the sunlight coincides with the spotlight.
- Dance-Off: Mechamato baits Karok by break-dancing to traditional and hip-hop music before inviting him to the stage. They dance in turns, and Mechamato equips himself with lights during Karok's turn to pull off an even more impressive performance that successfully outdoes Karok.
- Exhausted Eyebags: Amato develops dark circles under his eyes from being kept awake by noisy singing for several nights. On the night that he fights Karok, the robot causing the racket, several others at school also appear with eyebags the following morning due to all the commotion disturbing their sleep.
