The 999 stops at the Pitch Dark Planet, where all light is instantly absorbed. A while after Maetel leaves the train to "attend to private business", Tetsuro is beckoned outside by a figure at his window, who proves to be Miru, a daughter of the planet's ruler. She and her father tell him that Maetel has been kidnapped by Miru's sister Lelan, a deranged but brilliant scientist who plans to use Maetel's brain to launch an artificial sun into orbit, and that Maetel will die unless Tetsuro can infiltrate Lelan's base and kill her. Further, the new sun will doom most of the life on their world, which has never had light in its entire natural history. Tetsuro goes back for his gun, but is taken prisoner by Lelan the instant he steps off the train. His efforts to escape prove futile and Lelan launches the sun.
Tetsuro est sollicité par une femme pour tuer sa sœur Lelan qui tente de lancer un soleil artificiel sur la planète Dark-Dark, un endroit enveloppé dans l'obscurité de la nuit. Elle craint que s'ils ne savent pas ce qui se passera si le soleil artificiel est lancé et qu'il ne fait plus noir. Mais, Lelan enlève Maetel et met son plan en marche !
