Gon decides to take the Hunter Exam and become a professional Hunter, but can only do so after catching the Master of the Swamp to convince his aunt Mito. Despite her feelings after Gon catches it, Mito allows him to begin his adventure.
Gon's aunt Mito gives him the go ahead to take the Hunter Exam after he has successfully passed her test, using a special rod from his father. Gon goes to town to catch a ship to the exam.
On the ship to the exam, Gon and Leorio meet Kurapika. The captain asks each for their reason to be a Hunter. Gon wants to find his father, Leorio wants to be rich, and Kurapika wants to be a force for justice.
The ship's captain recommends to go towards a tree on the top of a mountain instead of directly at their goal. Leorio takes the bus and head towards the tree. The bus is a trap, so Leorio abandons it and catches up with Gon and Kurapika.
Gon, Kurapika and Leorio continue on the test, arriving at a cabin in the woods. A husband and wife say they have been attacked by beasts, when a beast shows up and kidnaps the wife.
Gon, Kurapika, and Leorio reach the first stage of the Hunter Exam, a seemingly endless forced run through a tunnel leading by the examiner named Satotz. They are befriended by a man named Tonpa, , and meet another entrant named Killua,
Tonpa has placed Leorio and another examinee near hallucinogenic sap. In a dream state, he explains that he wants to be a Hunter to get money so he can become a doctor who doesn't charge for his services. Gon and Killua bond.
Hisoka determines the real examiner by flinging deadly playing cards at each man, reasoning the true Hunter will live, and it's Satotz. Later, he plays at being an examiner and kills many examinees.
While one of the examinees, wrestler Todo, criticizes Menchi and all Gourmet Hunters, Netero, the head examiner and Hunter Association's president, arrives and asks Menchi to give everyone another chance.
The protagonists and others have passed the second stage, and they fly towards the next stage on a blimp. Anita, a girl who failed the earlier test, sneaks aboard to get revenge on Killua for the death of her father.
Killua stops trying to take the ball from Netero because his killer instincts are surfacing. Anita escapes her handlers and attacks Killua, who comes close to killing Anita, but lets her live because otherwise Gon would get mad at him.
The objective of stage 3 is to get down from a tower alive. The group is forced to team up with Tonpa, and their test is to win 3 out of 5 matches against tower prisoners.
Majitani feigns unconsciousness in an attempt to run out the clock. Leorio and the leader of the prisoners bet on whether he's faking. Leorio holds the man above a long drop, and Majitani wakes up.
Leorio goes next. His opponent is Leroute, an attractive woman. He loses ten hours in bet to her so that he can grope her. He then loses the rest of their betting hours to her in a game of rock, paper, scissors.
The last test to get out of the tower has two paths: one is too long and the other will only allow three of the five to enter. Leorio and Tonpa start fighting to see who will stay, when Gon thinks outside the box.
The hotel owners leave the examinees stranded on the island. A map is found indicating another island nearby, and part of the group sets out immediately to find it, dying when a storm hits.
The group works together to separate the battleship/hotel from the island before the second wave of the storm hits. Leorio gets stuck on the bottom of the ocean in a diving suit and Gon helps him escape.
The fourth stage of the Hunter Exam is a manhunt on Zevil Island. Each examinee must collect 6 points; their own number badge is worth 3, the number badge of their target is worth 3, and any other number badges are worth one point.
Gon and Killua continue their search for Hisoka in the Arena. They know that time is running out, as the tournament is rapidly approaching its final stage. They come across a group of shadowy figures who are also looking for Hisoka.
Gon finds himself in a tricky situation. He's trying to get to the location of the next phase of the Hunter Exam, but he's lost in the wilderness and running out of time.
A weakened Gon recuperates by resting and with some help from little animals, Killua is challenged by a group looking for his badge, Leorio's search for badge continues as the last day begins.
Chairman Netero interviews the nine remaining examinees in preparation for the final test. He asks each who they are interested in, and who would they least like to fight out of the nine.
Hisoka and Kurapika fight in the first fight of the final stage. Hisoka toys with Kurapika at the beginning, but when Kurapika becomes angry they are on similar levels. This causes Hisoka to force himself to calm down.
Hanzo and Gon continue fighting. Hanzo is easily the better fighter, but when Gon won't concede, Hanzo is forced to accept defeat. Hanzo decides he'd rather lose than kill Gon, because he likes his attitude.
Hanzo and Gon continue fighting. Hanzo is easily the better fighter, but when Gon won't concede, Hanzo is forced to accept defeat. Hanzo decides he'd rather lose than kill Gon, because he likes his attitude.
Satotz explains to Gon that Killua failed the final stage. His opponent turns out to be his older brother Illumi in disguise. Illumi questions Killua and determines him unfit to be a normal person.
Gon is determined that Killua has left against his will and is going to find him. He fights Illumi for information and Illumi is about to kill him when Hisoka shows up. Illumi instead tells Gon that Killua is at the Zoldyck family home.