Reverse's plot stretches further than anyone could have thought, as they plan to bring down not only the Letter Bees, but the entire Amberground government.
After Niche carries the wounded and stunned Lag back to the Bee Hive, the Letter Bee finally begins to piece the puzzle together. Now he knows what's happened to Gauche, why the Marauders are so focused on stealing mail and the actual intent of the group controlling both, Reverse. However, when he's forbidden to reveal the truth, Lag is soon forced out of the artificial sunlight and back into the world of perpetual night. And soon Reverse's plot to take down the Letter Bees and overthrow the Amberground government begins to accelerate. If things weren't already bad enough, the giant insect creatures called gaichuu are apparently evolving into something new; there may be traitors working within the Hive; and Niche's sister, who's definitely not human friendly, shows up to turn family drama into a full-scale siege. It all spells serious trouble for the Letter Bees, but if anyone can weather the storms and gloom of night, Lag and his team are the ones who'll deliver. The excitement continues as the man of letters who's also the ultimate man of action carries on fighting in TEGAMI BACHI: REVERSE.—Sentai Filmworks
Lag's quest to recover Gauche's heart continues, after finding him and being attacked in return he wakes up at Bee hive just to find that he has lost Gauche again. He must become stronger and a better Letter bee in order to be ready to take Gauche back next time he finds him. Along with his loyal dingo and friend Niche he is decided to make that dream come true and bring happiness back to Sylvette and Aria.—Anime News Network
AmberGround, a world of endless night. In this world where the darkness is full of dangers, Letter Bees stake their lives to deliver the mail entrusted to them. Lag is one such Letter Bee, following in the footsteps of Gauche, a letter bee whom he met and admires from a young age. Gauche has since been dismissed as a Letter Bee but Lag has sworn to bring him back. However, when they finally reunite, it is at opposite barrels of a gun as Gauche declares himself to be the bandit Noir.—AniDB
Still reeling from his chance encounter with the marauder Noir, Lag Seeing and his dingo, Niche must now attempt to unravel the plots of the mysterious anti-governmental organization Reverse in addition to their regular duties as letter carriers. Though dangerous, this task will undoubtedly lead them closer to finding the truth behind what became of Gauche Suede.—Anime-Planet