1970 manga (one-shot)
There are mass murders and catastrophes all over Japan, committed by a masked/caped psychic madman called the Skull Man, and his shapeshifting aide Garo (named after the manga ninja Garo created by Sanpei Shirato), who can mutate into various powerful monsters. The calamities caused by the Skull Man are investigated by the Tachiki Detective Agency, with the help of a young man named Tatsuo Kagura, the son of a yakuza in the Kagura Clan.
Police Chief Tachiki, who heads the Tachiki Detective Agency, suspects that Tatsuo is the Skull Man. Tatsuo, in turn, suspects that the detective is a part of a public conspiracy that has been after him for fifteen years. It turns out that Tatsuo's parents were murdered and he was adopted by the Kagura Clan. For fifteen years, Tatsuo has been hunting for the mastermind, who manipulates all industry, finance and even politics. Tatsuo, the Skull Man, threateningly demands Tachiki that he tell him the name of the mastermind. After muttering the culprit's family name, Chisato, the Skull Man shoots him in the head.
Skull Man and Garo then race to the estate of a reclusive old man named Kogetsu Chisato, who lives with a girl named Maya, who is mute and blind (she is always seen with her eyes closed). Overcome with psychotic rage, Skull Man threatens to kill Chisato, who not only kindly welcomes him, but has been looking forward to his arrival. Maya, however, telepathically persuades him not to kill Chisato, and reveals a shocking secret: Chisato is Skull Man's grandfather and Maya is his younger sister.
Chisato tells his shocked grandson the whole story: his own son, Tatsuo's father, was a scientific genius beyond geniuses. In fact, he was so intelligent and unearthly that he was a mutant, a being of Newmanity (Shinjinrui - similar to that in Ishinomori's later creation, Inazuman). His wife, whom he married and had Tatsuo with, was a mutant as well. The couple conducted bizarre experiments that were capable of destroying humanity. Chisato feared this greatly, so, when Maya was born, he killed his own son and daughter-in-law, and sought to kill his grandson Tatsuo, who ended up being rescued and raised by Garo. He could not bring himself to kill Maya, however, and raised her to be his faithful servant. Maya then tells Skull Man that Chisato wanted to bring him back before he could do anything.
Chisato traps himself, Skull Man, Garo and Maya in glass walls, and sets himself and all the others ablaze, sadly stating that "We were born in the wrong era!" Along with his entire "family", Tatsuo dies a tragic, horrible death in the inferno.
