The adventurer Rod possesses only a trash skill called "Unlock," which allows him to do nothing more than open locked treasure chests. Though constantly mocked by others, Rod dives into the labyrinth to fulfill his dream, only to be warped to the absolute bottom floor by a teleportation trap...! However, an unexpected encounter with a "God" on the lowest floor, combined with Rod's trash skill bugging out, causes his power to evolve into a cheat-grade ability...?! Conquer the "Five Great Labyrinths" with the weakest skill. The adventure tale of the "Fastest Labyrinth Conquest" proudly begins—!!