Tower Dungeon is a dark fantasy manga by Tsutomu Nihei, known for his intricate world-building and atmospheric storytelling. The story follows a young farmer named Yuva, who is thrust into a dangerous quest to rescue a kidnapped princess. The adventure begins when an evil sorcerer assassinates the king, usurps his throne, and kidnaps the princess, taking her to the legendary Dragon Tower. This immense and mysterious structure, which has mysteriously descended from the sky, is teeming with magical beasts and perilous landscapes, making it a daunting challenge for any adventurer.

Yuva, initially naive and unassuming, is recruited into a group of knights tasked with ascending the tower to rescue the princess. Equipped only with a pot lid for a shield and a strong will, Yuva embarks on this treacherous journey. As Yuva and his companions navigate the tower’s labyrinthine passages, they encounter grotesque entities such as shambling undead, monstrous human graftings, and uncanny automatons. The manga explores themes of survival, the resilience of the human spirit, and the horrors lurking within the tower’s depths.