A strange situation was unfolding in the Human Realm. Should a hole connecting the Demon Realm with the Human Realm be opened, innumerable demons would come pouring into the Human Realm. In order to close up the hole, Yusuke and the others have launched an investigation in Mushiyori City. There, they met Murota, who has the ability to read other people's minds. Using his ability, it would be easy to find any person harboring any strange thoughts. As Yusuke and the others took a position overlooking a busy street, they soon encountered a man with outrageous thoughts!

Yusuke asks Murota to tell them again what that man was thinking. Murota tells them all that the man was saying that they'll dig a grave for all people -the seven of them will dig the hole. Dark Angel, Gatekeeper, Sniper, Gourmet, Gamemaster, Doctor and Seaman. Kido says those must be their nicknames, and Genkai thinks the names must have something to do with their abilities as well.

Seven men with seven abilities... the man they saw earlier was probably one of them. Yusuke asks if there was anything else that man had on his mind, but Murota says that's all he could get out of the voice in the man's mind that offered any clues. Everything else was just an abnormal bloodlust, about wanting to kill everyone.

The group then sense something -someone has extended their territory, meaning there's someone here in the hospital with an ability. Murota says he can hear him, and whoever it is, they're one of the seven. They're also a doctor, and he's out to get them!

The group get together and try to figure out where he is, but there's no sign of everyone. Yana and Murota then feel something on their hands, and find a couple of demon insects have just injected something into them!

Yana crushes the insect, but whatever it injected into him starts changing his skin color to green. He and Murota fall down and say that they feel very cold, and it hurts all over. Murota says their attacker has created a virus, and can make people within his territory sick with it.

Genkai tells Yusuke and Kido to watch out, as there may be more. A swarm of insects head their way, and they have to swat them away.

A nurse then walks over and asks if something is the matter, unaware that insects are all around her. Yusuke and Yana tell her about them and tell her to brush them off, but she can't see them.

Yusuke realizes ordinary humans can't see the insects, and Genkai says this is going to get worse until they find whoever it is who's doing this. The three run off, and Kido says there's nothing but doctors inside the hospital. Yusuke suggests they just beat up all of them, and even Genkai agrees that'd be the quickest way -as long as they don't beat them to death.

Yusuke suggests they split up, which Kido agrees with. Genkai tells them when they find the guy, make some noise. Kido says he'll take the first floor, whilst Yusuke says he'll search the second. Genkai tells them to ask a nurse if there are any unfamiliar doctors in the building, as the doctor may not be someone who works here. They split up, and Kido finds a nurse immediately. He tells her that there's a criminal posing as a doctor inside this hospital. He tells her to come with him, and tell him if there's a doctor she sees that she doesn't know.

A doctor then walks in and asks what's going on, as they're going to disturb the patients. The nurse explains about what Kido just said, and the doctor says he'll call the police. Kido is fine with that -there's a dangerous person inside the hospital, who may be posing as one of the doctors here. One of his friends was injected by the guy, and is now in danger. Everyone in the hospital is now at risk! The doctor says he'll come looking with him, as he knows all of the doctors in this hospital. He tells nurse Takai to call the police.

She says she will, but then says she thought doctor Kamiya had the day off today. Kido realizes something is wrong, but before he can turn around, Kamiya rapidly hits several points on his back, causing him to fall.

Takai screams, but Kamiya calls her an idiot and slashes her. He tells Kido that he now can't move his arms or legs, and can't even talk. He's done something that's paralyzed most of the muscles Kido could move voluntarily. It's his ability -he can cut through human flesh with his bare hands like they were scalpels.

He does a small cut to one of Kido's wrists, and tells him he'll tell everyone that he was the one who attacked the nurse, and then took his own life. He says they'll eliminate every last person who would stand in the way of their wishes. But as Kamiya says this, another nurse walks in.

She screams, and Kamiya thinks he can't let this get too out of control. He tells her to go and call the police immediately, as there's a criminal in this hospital that's posing as a doctor. Elsewhere, Genkai is on the sixth floor, and can tell that every last corner of the hospital is enveloped in this guy's territory.

Yusuke heard the nurse's scream, and finds where Kido is. He sees that he's down, and another doctor asks him if knows this person. The doctor says that it looks like a man used a blade to attack the nurse and Kido. Kamiya is still in the room, but stays quiet.

Yusuke thinks one of these doctors could be the culprit, but then the attacker may have already ran away. One of the other doctors tells the nurses about the situation, and has them go and alert everyone else. Kido is still conscious but can't talk, which means he can't warn Yusuke that the enemy is right here! Yusuke tells Kido to hang in there, whilst he'll go and catch the guy right away and defeat him.

However, Kido suddenly extends his territory, and Yusuke suddenly can't move. He realizes Kido must be telling him not to go, and it must also mean the enemy is in this room! One of the other doctors says they need to treat Kido now and attempts to move him, only for Kido to use his ability to stop him.

Kido thinks he has to let Yusuke know somehow, and thinks of a way -using his shadow, he writes out the name of the doctor from the blood spilt from his wrist: Kamiya. The other doctors all turn around to stare at Kamiya.

But they all get slashed. Kamiya says there's been a change of plans: now he'll kill every person in the hospital! Yusuke is still trapped in Kido's territory, and Kamiya leaps forward. But Kido loses consciousness, and Yusuke is able to leap back just in time.

He realizes that when someone with an ability loses consciousness, the effects of their ability disappear. Kamiya says he wanted to play the role of the gentle doctor for a little while longer, but now his identity has been revealed to Yusuke, he has no choice. Yusuke sees that he knows him, and Kamiya says he heard about him from Dark Angel. He told them he and his friends would come to stand in their way, and spoil their dreams. In the Spirit Realm, Koenma and Jorge are watching.

Ayame then appears, and reports that there was a serious mistake regarding the center of the hole. It appears the hole is actually centered several hundred meters below the ground, and the energy involved is so great that it will take a little while longer to measure the precise location. He tells her to keep an eye on it, whilst Jorge wants to know what all this means. Koenma tells him that the situation could be a lot more serious that he anticipated.

Meanwhile, Kurama's group arrive in the city, and Botan isn't pleased with how many insects there are. Kuwabara wonders what she's talking about, as he can't see them, so Kurama has to explain. Kuwabara asks him if they're still being followed, but Kurama says whoever it was vanished before they got to the busier streets. He thinks whoever was following them may have gone over to Yusuke's group. Kaito thinks that Yusuke has probably met someone with an ability already, so they decide to hurry up and go and join up with Yusuke's group.

Elsewhere, Seaman reports to Sensui about Kurama's group. Sensui says at this pace, they'll all soon enter the Doctor's territory. They'll let Kamiya show Yusuke and the others how they fight against humans. Back in the hospital, a nurse starts to call the police, but some of Kamiya's insects inject her.

She falls before she can complete the call, and many people have also been injected by the virus. Puu, Keiko and Shizuru all arrive at the hospital, but they see main sick people at the entrance, and wonder what could have happened. Shizuru says she just sensed something strange about the space around them.

They wonder what could have happened, and Keiko thinks Yusuke and the others must be here. Puu then starts making noise and tries to warn Keiko by tugging her -he's seen two insects heading her way.

She can't see them, but Shizuru can, and she kills them before they can inject her. More insects start flying towards them, so Shizuru leads Keiko away. Elsewhere, Genkai encounters more insects, which she destroys. She wonders just what the hell is going on in this hospital.

Kamiya tells Yusuke that one of his abilities lets him make the people within his territory ill, using a virus creating by his own mind. His viruses are powerful, and death comes all the more quickly to those with weaker mental faculties. Yusuke's friends, who were the first to be injected, have no more than 30 minutes left to live. Yusuke says he'll defeat him before then, and batters Kamiya with lots of punches. Kamiya ends up crashing through a door. Yusuke tells him his abilities will disappear if he's defeated, so he'll do that now.

However Kamiya tells him that's quite impossible, and springs back up. He runs off and tells Yusuke to catch him if he can. Yusuke chases after him, but then loses sight of him.

Kamiya hides on the ceiling, and lets Yusuke pass under him before dropping down. Yusuke avoids his attack, which results in his projectile bouncing around the corridor.

Kamiya attacks with several rapid swipes, one of which cuts Yusuke's face. But Yusuke grabs one of his arms, and then punches him hard in his gut...

...before kicking him into a wall. Kamiya laughs and says that won't work, as Yusuke sees that Kamiya's moves and strength aren't that of any normal human.

Kamiya says when he first learnt of his ability, he thought of some ways to improve his body's functions. He can now control the supply of stimulants inside his brain at will, and as a result, he doesn't feel pain at all. Yusuke says that if he's turned into a monster, he doesn't need to pull his punches any more -something he was doing, as he though Kamiya was a human opponent. But it seems he won't have to do that any more. Kamiya says he'll dissect him, and runs forward. Yusuke prepares to use his spirit gun.

He fires a shot, and Kamiya tries to dodge it, but he's not fast enough. The blast severs one of his arms before shooting out of a window, where Kurama and the others see it. Kurama says Yusuke and the others must be at that hospital.

Yusuke tells Kamiya that he won't miss next time. Kamiya is impressed with the spirit gun, and says he can now see why Dark Angel told him not to be careless with him. He picks up his severed arm and reminds Yusuke that his ability is "Doctor". He reattaches the arm to himself, and heals it with his ability. He says that he can even perform reattachment surgeries on a whim.

(Yusuke is speaking)

Rotten Kamiya! What an incredibly horrible guy! Is he trying to kill everyone in the whole hospital? If he doesn't feel any pain, no matter how much I hit him, he'll never withdraw his territory! What is it that you're after?! Next time: Bring Down the Territory!! At this point, there's nothing to do but let him have it!