Cover of The Mark of Athena (The Heroes of Olympus, #3)

The Heroes of Olympus, #3

The Mark of Athena

by Rick Riordan


Genre
Fantasy, Young Adult, Children's
Year
2011
Pages
582
Contents

XXXVIII

Overview

Leo and Frank escape possessed tourists and reunite with Hazel in a hidden tunnel beneath the Pantheon. Leo solves a complex Greek lock using pi, revealing Archimedes’s lost workshop and scrolls. As hope rises, eidolons animate a sphere and armored manikins, incapacitating Hazel and Frank and trapping Leo.

Summary

Leo and Frank drop into a dark tunnel as the hatch seals, blocking the possessed “tourists.” Leo lights the way and worries the eidolons might still pursue by abandoning their hosts. They follow the passage south and find Hazel studying a mysterious gold-coated door etched with rings of symbols.

Hazel asks Leo to try the lock: a concentric ring sphere marked with zodiac signs, letters, and numbers. Recognizing Greek workmanship, Leo deduces it’s an Archimedean mechanism and aligns the rings to the digits of pi, reversing outward to inward. The door clicks open.

Inside lies a workshop filled with bronze-and-gold spheres, tools, cables, and two armored manikins. Leo identifies the place as tied to Archimedes and finds scroll cases, including On Building Spheres, realizing the lost secrets could help defend Camp Half-Blood and fight Gaea.

Before they can celebrate, a nearby orb activates, sprouts legs, and fires cables that shock Hazel and Frank unconscious. The “inert” manikins animate as the eidolons possess the machines, declaring Leo cannot escape and promising his death.

Who Appears

  • Leo Valdez
    Leads in the tunnels, solves the pi-based lock, discovers Archimedes’s workshop and scrolls, then faces eidolons animating machines.
  • Hazel Levesque
    Finds the sealed door, asks Leo to open it, is shocked and incapacitated by an activating sphere.
  • Frank Zhang
    Accompanies Leo, reasons about the eidolons’ loophole, is shocked and knocked out by the hostile sphere.
  • Eidolons
    Possess machines in the workshop, animate manikins, and threaten Leo after stunning Hazel and Frank.
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