Over the course of many books, the Cyborgs go from war zone to war zone: from undersea battles, to Vietnam, to the Middle East, to a subterranean lost world and so on and so forth. Finally, the author (Ishi(no)mori Shotaro) got sick of the Cyborgs and decided to end the series. The Cyborgs finally track down the mastermind of Black Ghost. 009 winds up in a spaceship in Earth orbit, and battles the mastermind. Well, the mastermind is an android, and the real mastermind is a set of 3 brains. 009 toasts them, too, but they die leaving the message "We are but a cell of Black Ghost, for as long as humanity loves war and death, there will always be a Black Ghost." 007(?) arrives, and the 2 leave the destroyed spaceship. Except oops, they're outside Earth's atmosphere, and 007(?) lacks the fuel to prevent them from burning up in re-entry. "Where do you want to fall?" he asks. Last few pages show a mother and son (or was it sister and brother) watching a falling star. The boy makes a wish for toy guns, but the woman makes a wish for world peace.
Well, except it didn't end there. Due to public reaction, the author continued the series (by saying that 001, a precocious baby psionic, had teleported the two cyborgs to safety). The rest of the series reads like a cross between the TV series "In Search Of" and a bad pulp magazine, following a trend that earlier books in the series had begun to follow. The cyborgs investigate strange, mysterious places around Earth, in the meantime getting involved in random short stories of varying degrees of weirdness. The theme of ancient high-tech lost civilizations, mad scientists, forgotten magical places, and aliens from outer space prevail. The plots aren't necessarily much good, but I'm used to Tezuka Osamu's masterful stuff, such as Black Jack (it doesn't help that Ishi(no)mori's artwork seems to be a takeoff on Tezuka Osamu's)... but, still, 009 must be given credit for being one of the earliest SF (and, I must say, occult) mangas in Japan.