Chapter 3 of Sasuke Retsuden: The Uchiha Descendants and the Heavenly Stardust (manga).
Summary[]
Just as Zansul threatened, the prison guards punished Sasuke everyday with brute force for attacking Menō the previous night. Sasuke didn't fight the guards back and instead took the chance of his latest punishment to steal a red cloth from one of them. This sudden behavior alerted Jiji, who back in their cells commented that Sasuke has recently become the guards' punching bag.
After his cellmates fall asleep, Sasuke decided to leave the cell with the red cloth tied around his hand; this would lead Menō to believe that he had permission to wander from the guards. While walking down the aisles, he found another prisoner tied up inside a locker and whose red cloth pass had been stolen by bullies. Sasuke gave the prisoner his red cloth so that he could go back to his cell safely.
Just as the prisoner ran, Menō arrived behind Sasuke. Engaging in a fight once again, Sasuke tried to use genjutsu on Menō to finally prove his suspicions, but the lizard was unaffected. He also noted that the injuries Menō suffered in their last encounter had vanished and he assumed it was thanks to a powerful healing ability. In one sudden move, Menō managed to scratch Sasuke's cheek, which prompted Sasuke to summon his sword and end the fight. However, after a few moments, Sasuke began to feel dizzy and his vision began to get distorted; he thought that Menō's claws might be coated with a poison native to Redaku. Sasuke escaped from the scene and found himself unable to move any further. His eyes were suddenly covered by his wife, Sakura, who had also infiltrated the prison without his knowledge.
Back in the prison's infirmary, Sasuke fully recovered from the effects of the poison. Sakura was revealed to be the new doctor. Sasuke asked about what had happened to Sarada, but Sakura reassured him by saying she was doing a home stay with Iruka Umino. Sakura continued by saying that the mission had changed and she handed him a letter she received form Shikamaru: In Redaku's capital, Kakashi had found information about the Sage of the Six Path's visit to Redaku and the Astronomy Institute centuries ago, and that during his stay, he saw a meteorite pass through the sky. By cutting the meteorite in half, the Sage of the Six Paths obtained the ultra-particles that cured him of his disease. He hid some of the ultra-particles in "the sky that fell to Earth" and Sakura thought that if they could find it and obtain them, then they could cure Naruto's disease. After reading the letter, Sasuke heavily suggested Sakura to go back to Konoha because he could handle the mission alone, but she insisted that he would need a partner for this sort of mission that required strategy.
They were interrupted by Jiji, who was seeking treatment for his blisters. During treatment, he questioned if Sakura was from around the area, as he had never seen somebody with her name or hair color. Just as he attempted to touch her hair, Sasuke grabbed Jiji's hand and stopped his flirtatious behavior. Jiji was surprised by Sasuke's presence in the infirmary, but he was even more surprised when he discovered that his cellmate and the beautiful doctor were married. Sakura quickly explained that she had decided to come to the prison to see her husband as a solution against the forbidden visits from relatives. Jiji understood why Sakura would do that.
On their way to the cell, Sasuke asked Jiji to keep his status as a secret. He confessed that his job prevented him from coming home, while Sakura was needed in their country; but he reassured Jiji that he didn't leave his home deliberately. Later, Sasuke asked him if he knew anything about a "Map of the Heavens", which he responded no. He suggested Sasuke to ask Penzila, the library attendant.