Galaxy Express 999

Keiko of the Insect Planet (1x93)

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The next stop of the 999 was the Insect Planet. It used to be paradise for insects before the humans colonization, and the Conductor warned Tetsuro and Maetel of the recent murders that have been taking place. Maetel and Tetsuro came a cross a man murdered, and his caged insects were released. They went to the house of Futoshi, Keiko, and their family, where Tetsuro saw the murderer ran into, but they did not find the perpetrator. In the following morning, Keiko met Tetsuro, and pleaded him to become an insect with her. A group of insect people appeared and tried to kidnap Tetsuro, but Maetel appeared and saved him. They returned to Keiko's home to find that she was transformed into an insect. She was, indeed, the one behind the recent killings. Keiko asked everybody to leave the house, blew up her room and killed herself.