Gon, Kurapika and Leorio arrive in the Republic of Padokea. They take a train that leads them near the town at the base of Kukuroo Mountain. Next, they ask a lady about how to get to the base. She suggests the three should take the tour bus. Inside the bus, there are two suspicious-looking criminals who can't wait to get to the mountain. The tourist guide, Coco Loo, tells them it will take two hours to get there. She then gives information about the Zoldyck Family. Kukuroo Mountain is actually a dormant volcano, standing 3722 meters; no one has ever seen the main mansion. She also knows that the Zoldycks have 10 living family members: the great-great-grandfather, grandfather, father, mother and five children, who are all assassins.
They arrive at the Testing Gate, also known as Gate to the Underworld. Coco Loo tells them no one has ever entered the Gates of Trial, and came out alive. They also cannot go nearer to the mountain as it is already the domain of the family. The two criminals from before tell the group that there's a bounty of 100 million for the one who can take a picture of a single member. They proceed over to the guardian and ask for the key. After a bit of struggle, they open the small door which leads to the main estate. The guardian worries about "Mike" having too much food. Once the two criminals are inside, they scream and the only thing the others can do is listen. Out from the small door, a gigantic hand throws out two skeletons of the criminals. Everyone on the tour runs in terror except Gon and his friends.
They introduce themselves as Killua's friend. It is a rare event that someone comes and visits the Zoldyck family. Zebro tells them that he can't let them enter because Mike, the guard dog of the Zoldyck's, will eat them. Mike only listens to the family members and was given the order to kill all intruders. He also tells them that the keys for the small door are only for intruders. The only way to enter without being eaten by Mike is to open the Gates of Trial. Zebro demonstrates to them how to open the first gate, which is 4 tons. He explains they cannot enter unless they have the strength to open at least one door. Gon asks him to lend him the keys, saying that being an intruder fits him better.
We learn that the Zoldyck Family has 10 family members, however only 9 of them are identified. The final member is only shown silhouetted in episode 24 of the 2011 anime. From this we can make out that the tenth member is a female and most likely the grandmother or great grandmother of the family.