Ayumu Narumi's older brother Kiyotaka, a renowned detective and piano player, disappears all of sudden. The only clue Narumi has, are the Blade Children. Two years later a row of murders and incidents begin, relating to the Blade Children. Together with school journalist, Hiyono Yuizaki, Narumi tries to figure out their destiny.

Alternative title:

• Spiral ~ Lines of Reasoning
• Spiral ~ Suiri no Kizuna (Japanese)

Spiral:

• 1. Spiral of Destiny
• 2. Seijyu: Hall of Death
• 3. The Cursed Children
• 4. The Fortune of Believers
• 5. The Misty Gallows of Death
• 6. The Blind Spot In The Net
• 7. A Choice of a Nonbeliever
• 8. Just a day of the Defeated
• 9. All Things That Are Possible To You
• 10. Only One Wise Action
• 11. Good Night Sweetheart
• 12. Dry Eyes
• 13. Overture [prelude]
• 14. Like A Sweet Aroma Haze
• 15. Like A Swan
• 16. The Uninvited Visitor
• 17. The Watcher in the Darkness
• 18. Angel of Sorrow
• 19. Mirror of the Heart
• 20. Whispering Shadow
• 21. The Sound of Heartbreak
• 22. The Mask's Confession
• 23. Never Ending Rain
• 24. The Man of the Lofty Castle
• 25. The Sound of the Thawing Iris