Indiana Jones puzzle reveals safe code through poem clues in Great Circle game

In "Indiana Jones and the Great Circle," players encounter the Father and Son safe code puzzle after rescuing Giuliana. This puzzle requires deciphering a diagram and recognizing a pattern from an Italian poem found in the Agency Room. To access the safe, players must use a key from Giuliana to unlock a door in the Borgia Tower. The correct safe code is 5873, which can be derived from a Polybius Square Diagram and a series of circled letters from the poem. However, one letter combination is incorrect, leading to confusion. Despite this, players can successfully open the safe by inputting the code 5873.