Mount Grimrock is a towering spire above the clouds, a weathered rock that has stood for ages. It is now a desolate place, remembered only when things need to be discarded and forgotten.

An airship struggles toward the peak as four prisoners, bound in heavy chains, emerge from the ship. The court accuses them of terrible treasonous deeds, but the king grants them forgiveness atop the mountain.

Their final trial begins at the top of the world, where many prisoners have received pardons before them, though none have returned. Plunged into the open maw at the peak, they must find a way through the dark and toward freedom at the base.