Upon his run-in with a Vouivre—a monster known to be very dangerous—Hestia Familia's captain Bell Cranel is struck with incomprehension. Despite its preceding reputation, the supposed bloodthirsty creature happens to be crying and flees from a group of adventurers. The monster, taking the form of a terrified little girl, prompts Bell to swiftly decide to hide her. Unbeknownst to him, this act of kindness will cause massive repercussions that will soon echo throughout the entire city of Orario.

The series adapts the volumes 9-11 of the light novel of Fujino Omori's series of the same title.

Dungeon ni Deai wo Motomeru no wa Machigatteiru Darou ka III was initially planned to broadcast in July 2020, but was delayed to October 2020 due to the COVID-19 pandemic.

The series was released on Blu-ray and DVD in four volumes from December 23, 2020 to March 26, 2021.