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Indiana Jones and the Great Circle

Secret of Secrets Puzzle and How to Solve

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Secret of Secrets is a mystery that involves opening the Vatican safe in the Sistine Chapel in Indiana Jones and the Great Circle. Read on for a complete guide on how to solve the Secret of Secrets puzzle and this Vatican safe code.

Secret of Secrets Puzzle Location

Located in Sistine Chapel

Map Location World Location

The Secret of Secrets mystery is centered on opening the safe in the office connected to the Sistine Chapel’s main hall. The Sistine Chapel can be found on the south side of the Vatican City map and accessed through the Borgia Courtyards.

Secret of Secrets Puzzle Solution and Safe Code

Secret of Secrets Solution Summary

All clues for figuring out the safe code in Secret of Secrets can be found in this office space.

1. Find the two notes—Nicoletti’s Letter and the Planetary Chart—in the office to get hints for the safe combination.
2. Inspect the statues of the saints. Use the notes you found to decode the symbols and figure out the safe combination.

Secret of Secrets Step-by-Step Solution

Secret of Secrets Step by Step Guide
1
Pick up the note called Nicoletti's Letter on the table outside the west door of the Sistine Chapel's main hall.
2
Open the drawer on the desk for another note holding the key to the puzzle. You'll notice that not all symbols have numbers beside them and there's an erased symbol at 4.

The numbers just go up by one as you move up the chart. The missing symbol is something you'll be able to figure out as you continue the puzzle.
3
Inspect the statue of Saint Peter in the corner of the room and Saint Paul on the table beside the safe. Rotate them until you can see the bottom of the statues, and match these symbols to the Planetary Chart. The missing symbol beside 4 on the chart is the one that can be found on Saint Peter.
4
Using the symbols on the statues and the numbers on the Planetary Chart as a guide, you should be able to put together the code. The Secret of Secrets safe code is 4471.

List of All Unlock Codes

Secret of Secrets Safe Contents and Rewards

Sistine Chapel Safe Contents

Upon opening the Sistine Chapel safe in Secret of Secrets, you can obtain the Cutman I Adventure Book, which improves your health bar regeneration, as well as a Hidden Note.

The "original copy" of the book in this safe is actually a fake and is of no use to you.

List of All Books

100 Adventure Points Reward

Secret of Secrets 100 Adventure Points Completion Reward
Completing the Secret of Secrets mystery rewards you with 100 Adventure Points, not including the Adventure Points you gain from collecting the clues to this puzzle.

Indiana Jones and the Great Circle Related Guides

Puzzles

List of Puzzles

The Vatican Puzzles

Adventure Puzzles
Sacred Wounds Fountain of Confession Gold Path Trial
Silver Path Trial
Mysteries and Misc. Puzzles
Belvedere Chest Code Secret of Secrets House of God
A Snake in the Garden A Date to Remember Signs of Trouble
A Free Spirit Father and Son Post Office Cellar Lockbox

Gizeh Puzzles

Adventure Puzzles
Nazi Vehicle Garage Chest Chamber of Resonance Three Eyed Gate
Fieldwork Puzzles
Secret of the Queen Mother Mural Gold Mask Mirror Puzzle Statue of Light
Mysteries and Misc. Puzzles
Cloud Atlas Seat of Eternity Bright Future
Fortune's Reach Locked House Wehrmacht Chest
Egyptian Numeral Chest

The Himalayas Puzzles

Adventure Puzzles
Kummetz Cipher

Sukhothai Puzzles

Adventure Puzzles
Voss' Gold Stash Safe Hidden Gate Nephilim Game
The Great Game
Discovery Puzzles
Khmer Cogwheels
Fieldwork Puzzles
Khmer Pipeworks Prayer Wheel Symbol Pedestal (Sealed Sarcophagus)
Mystery Puzzles
Path of Tigers Child's Play The Serpent's Chest
Counting Letters Monkey Business A Timely Arrival
Elephant in the Room A Game of Wits

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