"The Night Before the Second Exam" (二次試験、前夜, Niji Shiken, Zen'ya) is episode 398 of the Naruto: Shippūden anime.
At night in Sunagakure, a masked individual breaks into the Kazekage's office building. Kankurō confronts him, and questions his identity, which he claims to be one of the extremists seeking reform in the Land of Wind. As the assassin makes his escape, Kankurō pursues him. Seemingly cornered, he attempts to commit a suicidal attack, but Temari arrives in the nick of time to save Kankurō. The next morning, Kankurō and Temari alert Gaara that his rebels are stepping up their efforts against him, but the Kazekage refuses to cave in under pressure. Elsewhere, the main teams of the Konoha 11 all arrive safely to the Demon Desert checkpoint to secure their qualification, while those that arrive late are eliminated and are instructed to return to their respective villages. During dinnertime, a fight breaks out between the genin after the Konoha shinobi accidentally ruined the food. As Fū arrives and is seemingly hoping to make friends, the other genin leave the cafeteria, much to her dismay. Back in Konohagakure, Kakashi reports to Tsunade of his failure to infiltrate Amegakure, suspecting the state of things after having not met Hanzō in person. Meanwhile, Chōji sneaks out to the building where the jōnin are, hoping to get food. Sakura and Ino follow him, and they are all attacked by a giant scorpion. Fortunately, Fū arrives to their rescue. Arriving to the scene, Gaara notices the similarity between Fū and Naruto due to her unique charisma. The next day, the second phase begins, and, as in the previous Chūnin Exams, half of the teams are given the Scroll of Earth, while the other half are given the Scroll of Heaven, meaning each team must retrieve the counterpart scroll to pass the exam.
Even though it takes three days to travel to Suna from Konoha, no matter the route, Kankurō and Temari were able to reach the village in two days.
A kunoichi from Suna in one frame was shown to have failed the exam as she didn't make it to the Demon Desert in time and in the other frame was shown sitting with her fellow Suna genin, albeit with a slightly different colouring palette. Whether this was on purpose or an accident is unknown.