Ōnoki's Thoughts, Kū's Thoughts

Slipping through the dark to dodge the Akuta, Boruto and Ōnoki trip a set of barrier tags. Come morning, Ōnoki puzzles over why the boy bothered to save him and again presses his case that today's young shinobi have grown soft and unreliable. When Boruto tries to walk off, Ōnoki reveals they stand in the Sanzu Plains, ringed by a barrier that traps anyone inside until they locate their heart stone, an ordinary pebble found only through grueling training. Boruto's shadow clones are useless here, since the barrier blocks jutsu, and Ōnoki notes that no one visits the plains anymore, so rescue from outside is unlikely.

Kokuyō and Kakō report to Kū that Ōnoki is still missing. Kū orders more Akuta into the hunt, trusting Kirara to keep the villagers oblivious, and rejects Kakō's idea of silencing witnesses as a betrayal of Ōnoki's aims. Sekiei tells Mitsuki that Leaf shinobi came searching for him but Kū drove them off, and Mitsuki asks to meet Kū. Sarada and Chōchō, learning that Boruto and Shikadai never reached the rendezvous, grow worried amid the swarming Akuta. In the plains, Ōnoki shares food and water with Boruto in thanks and keeps pushing the notion that comfortable, book-taught youth have lost their edge, which Boruto challenges by asking whether wartime truly made them better.

Ōnoki clarifies that his real point is the worth of hard experience, citing the Ōtsutsuki threats Boruto has faced, and reveals that he built Kū from his own cells and summoned Mitsuki because similar technology shaped him. Meeting Kū at last, Mitsuki points to the cursed seal on his heart, which Kū dismisses as an old measure they can eventually bypass, and the two turn to debating the nature of will in synthetic beings, with Kū suggesting Mitsuki put the question to Orochimaru. As Kakō and Kirara begin to malfunction, this Boruto episode of Mitsuki's Disappearance arc closes on another night in the Sanzu Plains. It aired in Japan on December 2, 2018.