The victims of Gargoyle's latest attack are taken to the long-forgotten underworld of Atlantis to be buried. While there, Jean discovers that his father's ship was sunk by the Garfish. Nadia also learns that she must keep the Blue Water at all costs, no matter what pain or damage it may cause.

Four months afterward, the Gratan is nearly repaired, and soon our pals will set off for Africa. But first Jean and Nadia go off on a hike which leads them to a mysterious underground cavern that turns out to be more than they suspected. The exploration culminates when Nadia falls into a trance and vanishes behind a wall, leaving her clothes in Jean's arms! During all this, Ayerton tries to make his move on Grandis.