There is a prison from which, it is said, no one attempts to escape. The reason is that the prison is guarded by Iron Lizards, which are self-propelled bombs that pursue people anywhere, based on genetic data stored in a computer. Lupin and company learn that Fujiko is inside held by the warden, who wants to have sex with her. In order to save her, Lupin, Jigen and Goemon get inside the prison, but end up captured by the warden who enters their genetic data into the Iron Lizards.