The Enigma of Amigara Fault (阿弥殻断層の怪 Amigara Dansō no Kai?, Amigara means "Empty Shell") is a short manga by Junji Ito. It was published along with the second volume of Gyo, but has nothing to do with the story. The entire tale is shorter than the length of the average manga chapter. The characters undergo a Lovecraftian sense of being inexorably drawn to their doom due to curiosity of the mystical and otherworldly. Like fellow manga artist Shintaro Kago, Junji Ito's work is concerned with confronting and destroying the sacredness of the body.
The story begins as two young hikers named Owaki and Yoshida meet on Amigara Mountain. They had both seen the mountain featured on the news, and wanted to investigate the story for themselves. Recently, an earthquake had split the mountain and raised a large cliff face from the rocks. Dug into the cliff face, apparently naturally, are thousands of deep holes shaped like life-sized human silhouettes. The phenomenon, as Owaki and Yoshida discuss, has been the focus of international attention since it was discovered.
The two reach the fault, and find a large crowd of people gathered there. Scientists examine the holes and decide that they could not have occurred naturally, but cannot figure out where they came from. The human-shaped tunnels extend far into the mountain.
Owaki notices Yoshida looking for something, and she tells Owaki about how she had seen a hole on TV that was shaped exactly like her. A man named Nakagaki overhears, and tells the same story. He has already found his hole, and as the two teenagers watch, he strips off his clothes and slips inside. The hole is angled slightly downwards, and Nakagaki slides deep into the mountain as the crowd watches in horror. A rescue squad attempts to go in after him, but the man sent into the hole to rescue Nakagaki is forced to turn back after going in only five meters.
Owaki pitches a tent and sleeps on the mountain, but has nightmares about Nakagaki being stuck hundreds and hundreds of feet deep into the hole, crying out for help but unable to escape or be helped. When he wakes up, he finds Yoshida, who has found her own hole. Suddenly, there is a commotion. Another man has climbed up the wall in his underwear, and is clinging to a hole shaped like him. The crowd yells at him to get down, but he cries out, "This is my hole! It was made for me!" More people start entering their holes, and Yoshida becomes frantic. She's convinced the hole is calling out to her, so she and Owaki fill it with small rocks. They then go to sleep in his tent.
That night, Owaki has another nightmare. He dreams he is a criminal in some ancient time, and his punishment is to enter a hole shaped like him. As he moves down the tunnel, the shapes in the rock for his neck and limbs begin to stretch, and his body deforms along with it. Soon his entire body is long and thin, and his limbs look the shape of tentacles. His head is a few feet long, and yet he remains alive.
The next day, Owaki discovers Yoshida has removed the rocks from her hole and entered it. He calls for her, but there is no response. Saddened and confused, he sees his own hole, and fits himself into it.
Several months later, another cliff face is discovered on the other side of the mountain, parallel to the first one. This one has holes as well, but not the perfect human silhouettes that the other side had. They are vaguely human, but the limbs are so thin and stretched out that they resemble worms rather than arms or legs. One worker shines his flashlight into one of the holes. He sees something alive coming down the tunnel, its face twisted and squashed against the rock, its arms extended to unnatural lengths and curved.