Dungeon ni Deai wo Motomeru no wa Machigatteiru Darou ka IV: Shin Shou - Meikyuu-hen

Orario, the Labyrinth City—An enormous city that harbors a vast underground labyrinth known as the "Dungeon." It is here that a young boy who aspired to become an adventurer met a tiny goddess, made friends, challenged the Dungeon, and narrowly escaped death on several occasions, all while leveling up his skills.

That very same boy receives a letter.

It contains a mission– an expedition into the Dungeon, deeper than he's ever gone before.

Facing uncharted territory, the boy sets out alongside his friends on a brand new journey.

This is the story of a boy as told by a goddess– a "Familia Myth."