Kasekitou is an omnibus story featuring the dreams of three travelers who visit Fossil Island. They are Rock, a newspaper reporter, Kodama, a songwriter, and Tezuka Osamu, a cartoonist.
There are many strange rocks on the island that look like human figures. After they see the rocks, the travelers have strange dreams associated with the rocks. Rock dreams that he becomes partner to Sherlock Holmes and fights against the phantom thief Lepin for a hidden sculpture. In his dream, Tezuka Osamu, by eating ancient foods, goes to a world where humans have animal brains and animals have human brains. Meanwhile, Kodama, in her dream, is robbed of her body by Eros, the god of love, and goes to Heaven.