Neuro is a being from the underworld, who likes to eat "riddles" and "mysteries" and since he had heard that mysteries abound in the world above, he comes surface side in search of the ultimate riddle capable of satisfying his insatiable hunger. He arrives in front of Katsuragi Yako whose father has been murdered, and smells a tasty riddle... He agrees to help her to solve the murder of her father and in turn forces Yako to act as a detective in his stead, always searching for the ultimate riddle. Groups: Episodes 1-7 Catchphrase and Episodes 8-25 Ainex. Video: Catchphrase - 1280x720, 16:9, H264 AVC, ~1,531 Kbps 29.970 fps and Ainex - 1280x720, 16:9, H264 AVC, ~1,300 Kbps 23.976 fps. Audio: Catchphrase - Japanese Vorbis \[128 Kbps\] and Ainex - Japanese HE-AAC 2.0 \[112kbps\]. Subtitles: Catchphrase - Advanced Sub Station Alpha \[.ASS Softsub\] and Ainex - Advanced Sub Station Alpha \[.ASS Softsub\]..