While teacher Kakashi directs his furtive students by the use of earphones and microphones, they follow a lurking shape in the forest. When they finally pounce onto their target, it resolves into a household cat. Kakashi concludes: "operation capture Tora the lost pet complete." Naruto complains: "Isn't there a more important mission we can work on?"

     

Back at ninja headquarters, while the cat is reunited with its owner, Hokage-sama reads the next missions to his new recruits: babysitting, grocery shopping, digging up potatoes... Naruto lets out a yelp. He wants something important.

Hokage-Sama explains that many clients come to the village daily requesting missions that range from easy to dangerous. It is his job to separate the missions into classes, the most dangerous being assigned to the Jounins, the second and third classes assigned to the Chuunins and the easiest relegated to the junior-ranked Genins.

When Naruto indicates that he is no longer a kid pulling pranks, Hokage-Sama relents, and assigns them a more challenging mission. They are to escort Tazuna, a bridge builder to him home town. The old bridge builder enters, but is unimpressed by his guides, referring to Naruto as the small one with the idiotic face. Naruto jumps up and proclaims: "I'm going to kill you!"

In his usual dry fashion, Kakashi advises not to kill the man you are supposed to escort.

The journey begins, and they pass out through the fortified gates. It is the first time Naruto has ever left the village. As they leave, they are watched from the trees by mysterious eyes.

During their journey, Kakashi explains that not all villages have ninjas. There are hidden villages where ninjas exist, these villages being the equivalent of a country's military power. The countries that have ninjas are represented by the elements: fire, water, lightning, wind, and earth, and are known as the Five Great Ninja Powers. The first is their own village: the country of Fire's hidden village of Konoha ("leaf"), the second being the country of Water's hidden village of Mist, the third being the country of Lightning's hidden village of cloud, the fourth being the country of Wind's hidden village of sand, and the last being the country of Earth's hidden village of rock. Each has a leader known as Kage, yielding the titles: Hokage, Mizukage, Raikage, Kazekage, and Tsuchikage. These are the Five Kages who reign over the tens of thousands of ninjas in the world.

As they walk through the forest, Kakashi spies a puddle that appears unusual. After they have passed by, from out of the puddle emerges two cloaked and masked ninjas, who immediately attack the group from behind. They launch a metal chain from an throwing weapon. The chain binds Kakashi, immobilizing him. The earth then opens up and sucks the teacher beneath. They refer to him as the "first one," and they now turn their attentions to Naruto, referring to him as "the second." They launch the chain again. The terrified boy is unable to defend himself and is quickly injured. From his side, Sasuke makes a move, launching his weapons which pinion and disable the chain. Sakura positions herself before the old man, attempting to protect him from the next assault. Sasuke then dashes toward the attackers, striking them repeatedly, but he is no matched for the experienced ninjas. Suddenly Kakashi reappears, snags the attackers by the necks, and they fall limp and unconscious.

The teacher had avoided the initial assault through a replacement technique, transforming himself into images of wooden logs which received the attack from the chain before they were broken and destroyed. For their efforts, Sasuke and Sakura receive praise, while Naruto only concern for his injury, the boy having been too paralyzed by fear to participate in the defense of the group. Sasuke asks if he is hurt, then refers to him slyly as, "Scaredy Cat." Naruto is angry, but Kakashi intercedes, warning him that the attackers have used a poison, and he requires medical assistance.

Kakashi explains that the attackers are Chuunin-class from the hidden village of Mist. As they revive, they groggily ask their captor how he detected their presence. Kakashi replies that it hasn't rained for the past few days, and today it is sunny, therefore the puddle should not have existed. The old bridge builder wants to know why he let the children fight. Kakashi explains that although he could have defeated the attackers at any time, he first needed to know who the real target was. He correctly surmises that the old bridge builder has not been honest with them. The purpose of his escort had not been protection from robbers, but from ninja, redefining this as an expensive mission of a much higher rank.

Believing they must quit this dangerous mission, and needing to take Naruto back to the village for medical attention, they suggest going back. The embarrassed boy objects to being treated like a burden and takes out his knife, stabbing it through his hand to bleed off the poisoned blood. He stubbornly concludes that he will never again require anyone to help him, that he will not be frightened, nor will he back out of a fight. He vows by the pain in his left hand, that he will protect the old man with his kunai (throwing knife).

Kakashi remarks, "it is nice you took out the blood so spiritedly, but you're going to die from loss of blood if any more comes out."

Naruto panics and is about to pass out. While Kakashi binds his wound, he observes that it is already starting to heal. Without telling the others, he suspects that it must be by the powers originating from the Nine-tailed Fox sealed within the boy.

Back at the enemy's camp, the man who has hired the assassins berates his men for their failure. A dangerous-looking ninja says that he will use his decapitating sword and go and kill them himself. Even though the Group of Seven and the bridge builder will now be on high alert, he, "Momochi Zabuza", will not fail for he has been called the Demon of the hidden village of Mist.