The Shinobi Prison: Hozuki Castle

Synopsis
A group of prisoners are taken by boat to Hōzuki Castle, where they are branded by the warden, among the prisoners are Boruto and Mitsuki. Mujō explains their new status as prisoners, and leaves Benga to give further explanations. One of the prisoners attempts to escape, activating Mujō's jutsu. Boruto and Mitsuki think back to being assigned a mission to infiltrate the prison, and collect information on who the leader of the Mujina Bandits is from a former member before the bandits can have him killed inside. Boruto and Mitsuki were sent because arrangements to have Kokuri protected inside would take too long, as Kusagakure, who administers the prison, hasn't been targeted by the Mujina's crimes, so they don't feel obligated to prioritise obtaining that information. Konohagakure was able to arrange with the master of the prison to have a fake brand applied to Boruto and Mitsuki. Sarada is to infiltrate the prison by posing as a journalism student conducting research. Boruto and Mitsuki are introduced to their cell-mates, and claim to be from the Land of Water, serving eight years for robbery. Benga shows Sarada around and answers her questions. He believes Mujō is too soft on the prisoners because he thinks they can be rehabilitated. Arai shows Boruto and Mitsuki who can smuggle things in for them. They learn that the Mujina's number two, Tsukiyo, is in solitary after getting into a fight with Kokuri, the defector they're supposed to protect, who was sent to the medical ward. Arai explains it's difficult to be sent there, but that eating the poisonous plants that grow around the prison should be enough. Mitsuki manages to grab one with a snake during recreation time. Boruto eats the poisonous fruit and is sent to the medical ward. Boruto wakes up in the medical ward a day later, but is knocked out by Kokuri when he asks for him. Boruto wakes up again, restrained by Kokuri, who thinks he's there to kill him. Boruto explains Konoha got his letter and sent him. Tsukiyo communicates with someone from solitary through notes. As Boruto is escorted back to general population, someone sneaks into the medical ward, and stabs Kokuri on Tsukiyo's orders.

Trivia

 * The episode appears to resolve an inconsistency regarding Hōzuki Castle. When introduced in Naruto the Movie: Blood Prison, it was said to be located in Kusagakure, which is located in a landlocked country, despite being located by the sea. In the episode, it is said to be administrated by Kusagakure instead. However, there also appears to be no mention of the events of Kakashi Hiden: Lightning in the Icy Sky.