While most of Amberground remains blanketed by perpetual darkness, the capital city of Akatsuki basks in the light of an artificial sun.  But as Lag Seeing's investigations deliver him to the doorstep of Houdi Franklin, survivor of an ill-fated airship journey on the infamous Day of the Flicker, the secrets behind the light in the sky begin to cast dangerous shadows on the Letter Bee's future.  Yet the death and blindness unleashed by the abomination in the heavens are only the first salvos in Lag's greatest series of challenges to date.  The molten Gaichuu monster Cabernet is still on the loose, wreaking havoc and destruction.  The sinister organization Reverse has agents working behind the scenes everywhere, attempting to undo the fabric that holds Amberground's society together.  The Bee Hive, headquarters of the Letter Bees, is itself abuzz with treachery, and the restoration of Gauche's memory may be about to come back on them as a double-edged sword.  Can Lag, Niche and Steak cancel out each of these incoming dangers and return them to their senders?  The answers await in the final, illuminating collection of TEGAMI BACHI: LETTER BEE REVERSE!