Duniya da aka rasa

Kasancewar an tsattsage daga duniya a zamanin da, Planet Mamango yanzu yana sake zuwa duniya bayan ɓacin shekaru miliyan 5. Wata rana da daddare, wani jami'in sirri mai zaman kansa mai suna Ban Shunsaku ya gamu da kisan kai, kuma ya hadu da yaron mai binciken Shikishima Kenichi, wanda ke rike da mabuɗin warware matsalar. Shikishima ya gano cewa dutse daga Planet Mamango yana samar da kuzari mai yawa. Yin roket daga dutsen makamashi, Shikishima ya kafa ƙungiyar masu bincike kuma ya tashi don Planet Mamango. Rokar ta nufi kai tsaye zuwa Planet Mamango a ƙarƙashin jagorancin Shikishima, tare da Kyaftin Butamo Makeru, Ayame da Momiji, waɗanda kabeji ne waɗanda kaftin ɗin ya ƙirƙiro, wani zomo mai suna Mii, da Ban Shunsaku. A lokacin da ya dace, roket din ya fada kan Planet Mamango, inda kungiyar ta sami "The Lost World," wani tsohon wuri ne inda dinosaur ke tafiya kuma fern da cycads sun rufe ƙasa.
Lura: Sigar da aka fi yaduwa (gami da na Turanci) ita ce ta 1948, wacce Fuji Shobou ya buga kai tsaye. Wannan maimaitawa ne na jerin da Tezuka bai kammala ba wanda ya rubuta wa Kansai Kyouron Shinbun a 1946, wanda aka rasa. Ya sake shirya jerin a cikin 1955 don Bouken Ou a ƙarƙashin taken "Zenseiki Hoshi", amma wannan sigar ma ta ɓace.