"The Shadow of the Mastermind" (黒幕の影, Kuromaku no Kage) is episode 11 of the Boruto: Naruto Next Generations anime.
The Academy students visit Sumire at the hospital. Wasabi and Namida thank her for saving them, but Sumire credits the Hokage for being nearby. Shino feels guilty as the work experience classes were his idea, though Chōchō just tell him to learn from it. Iwabee points out the frequency of the attacks, Denki and Lee sharing their experience on how it felt. Boruto arrives, and apologises profusely to Sumire, feeling responsible for the situation. Shikadai tries talking to Boruto, who insists that if had delivered the mail properly, they would have had the entire day to patrol, and might have seen something at the water purification plant. Naruto arrives, and when Boruto asks him to loop him in on the investigation, Naruto drags him to another room, showing Sumire's attacker, nearly drained of all chakra.
They discuss what Boruto should or shouldn't do. Shino claims responsibility for the workplace experience classes, suggesting that if treated as an adult, Boruto might be able to show them something they can't see, and that as Boruto's teacher, he knows what he can and can't do. Naruto leaves the decision with Shino. Shino doesn't give them a free pass, but as they have saved him before, he has respect for them. Boruto, Mitsuki and Shikadai go back to the post office, and are surprised when Komame tells them to deliver mail. Tayori intervened on their behalf. When looking at delivery routes, Boruto considers having shadow clones take all of them, but his own clones think it would put too much distance between them. The three deliver mail through the village. Sumire bids Wasabi and Namida goodbye, and watches from the window as they leave with their parents. Mitsuki arrives with information on the latest attack. At the scene, Sai finds more trace evidence of Wood Release use. Sai wants to investigate possible Root involvement as soon as he can, to make sure that if Root is involved, whoever is behind it doesn't follow the same ideology as he once did. After they miss another attack, Boruto considers the possibility the ghost knows their route. To cover all the mail routes at once, Shikadai asked the help of their classmates, and to notify them if anyone finds an incident, he had Iwabee bring fireworks from his workplace experience. After they leave, Komame just misses someone at the post office, is possessed by the ghost, and begins wrecking the post office. Boruto and the others arrive, having successfully tricked them into believing all the routes would be watched, leaving the office unattended. Boruto prepares to fight Komame, while Mitsuki, Inojin, Chōchō and Lee chase the one controlling the ghost. Komame uses the mail to attack Boruto and Shikadai from a distance, which Iwabee blocks with Earth Release. Tayori protects one of the parcels from Komame's attack, and his dedication to it weakens the ghost's hold on Komame, allowing Boruto and Iwabee to knock him out. The ghost leaves Komame, and Boruto throws an explosive tag at it as it disappears. The masked men controlling the ghost loses the others. Mitsuki finds him, but the two don't attack each other, and Mitsuki lets him leave. Komame is taken away, and Boruto leads the others in reorganising the post office. Something comments on the chakra being stolen being used to awaken Nue.