The old town of Tokyo is buried under water following a terrible catastrophe which has occurred several years before. Aika and her young partner Rion work for an agency specializing in the recovery of old relics, but the owner has serious financial problems. This is why it was decided that Aika again take up her old activities as a special agent...

Aika has been entrusted with a mission of collecting information on a material called "Lagu", but its progress was stopped by Hagen and his sister Neena, which have other projects for Lagu. Held captive on their vessel, Aika and Rion do what they can to try to escape. But it seems that the capacities of Aika are ineffecient against the new weapon of Hagen.

Aika with the assistance of her friend Gusto, succeed in escaping from the ship, leaving behind Rion. Her last combat left her weakened and she is no longer any match to face Hagen and his crew. During this time, Rion and Maypia, a spy whom they met, try to escape, but the projects of Hagen have already started to be carried out...

The team of Aika finds themselves involved in space in the hope to carry a term to the intrigues of Hargen of which all the parts are in place to put at execution its terrible plan. But quickly Aika will be confronted with an adversary of size, Neena. which carries on it an object which confers to him capacities semblabes with those of its gilded long-line bra from now on inoperative. The combat is announced hard