"Is that a spider?!"

[Book 5]

Twenty-Four Hours. That's exactly one day to prevent the end of the world and defeat Night.

The crew of the Argo II is divided, half trapped within the North Mountain, half caught hanging over a mob of Darkness-devoted monsters. Along with the certainty of a trap, they are suspicious of their guide, Percy Jackson. But there's only one way to win this, and said guide has made himself indispensable.

The journey is almost done, but the war isn't over yet.