The anime series is set in the future when humanity migrated to the Moon due to Earth's climate change. It will incorporate original elements unique to the anime, such as human drama about survival, and will feature a diverse field that blurs countries and eras such as Shibuya, the Edo-period era, and London.

The dark-haired bishounen is Sakon Tachibana, a puppeteer, and the other is Ukon, his favorite puppet, and best friend. Sakon is the (only) grandson of Saemon Tachibana, a national treasure of Japan famous for his manipulation of Bunraku puppets. Ukon is a child doll puppet made in the early Meiji era by the famous female dollmaker Unosuke. Together they run into murders and solve them.

From time immemorial to the age of space colonization, there is one legend that has stayed unchanged in every history book—the tale of the immortal bird Phoenix. A being whose blood is said to grant eternal life or wisdom, the radiant figure ensures the continuation of sentient life in the universe as it oversees human civilizations and their development. Yet, mankind remains a slave to its habits; from happiness and sorrow, to wrath and love, a myriad of emotions continue to play an integral part of human life. Simultaneously, time and time again, certain beliefs and agendas persist over the centuries to disturb the fragile equilibrium of the world's preordained nature and principles. It appears that fate and its dynamic variables can manifest itself in many ways—and oftentimes exhibits a bizarre sense of humor...

The third season of Youkoso Jitsuryoku Shijou Shugi no Kyoushitsu e. The third semester kicks off in high gear with a special boot camp deep in the mountains. Forcibly separated into groups along grade and gender lines, the first, second and third years alike must work together to survive the rugged terrain. Even worse? The leader of the group that comes in last will be expelled. Can Class D make it back to campus intact, or is this where they finally say goodbye to one of their own?