"The Quietly Approaching Threat" (忍び寄る脅威, Shinobiyoru Kyōi) is episode 72 of the Naruto: Shippūden anime.
Asuma visits the grave of his father, Hiruzen Sarutobi, and recalls an old memory in which he fought against his father for not acknowledging him for protecting the king of the Land of Fire. Hiruzen had berated him for still nor understanding what or who the king truly was, and at his grave, Asuma tells his father that he finally understands. He leaves his lit cigarette at the grave and walks off. Meanwhile, in Tsunade's office, Shizune alerts the Hokage that Kakashi, who had been sent to find word on the Akatsuki as well as locate Jiraiya, has returned to Konoha and has compiled a report.
In the hospital, Sakura cuts some apples for Sai to eat, which the latter interprets as Sakura having a crush on him due to the book he is reading. Naruto, asleep in the next bed, dreams about Sakura feeding him. Sakura then jams an apple in his mouth, nearly causing Naruto to choke, as Kakashi walks in. Naruto prepares to leave the hospital so that they may train but Kakashi warns him that the next stage would be arduous that leaving the hospital without fully recovering would result in dire consequences. Asuma then shows up, asking for a private moment with Kakashi. As he leaves, he appoints Sakura in charge of the two boys.
Outside, Asuma and Kakashi reminisce how Naruto's generation has grown to the point where they were able to successfully fend off an attack on the village. Kakashi muses that it won't be long before they leave the older shinobi in the dust, and Asuma counters that he still has some good years left in him. Before he can tell Kakashi what was on his mind, they are interrupted by the arrival of Kurenai; Asuma tells Kakashi that they shall discuss the matter later, which piques Kakashi's interest. Kakashi is later summoned to Tsunade's office, where she asks if Naruto is truly capable of learning and mastering a new technique. Kakashi tells her that he is not certain, but he believes that Naruto will most likely succeed.
Elsewhere, Yugito Nii, the Two-Tails jinchūriki, is confronted by Hidan and Kakuzu, two members of the Akatsuki sent to retrieve her. After trapping them in a cave using explosive tags, she enters her tailed-beast form, unleashing the power of Matatabi, the Two-Tailed Cat Spirit. Using the power of her tailed beast, she attempts to hit Hidan with her Cat Flame Roaring Fire. Hidan claims that he is not amused and that the battle would be significantly harder. However, some time later, Hidan is able to use his Retractable Spear along with his Jashin rituals to impale himself and wound Yugito to the point where she is rendered unconscious, allowing the Akatsuki members to complete their mission.