Code 0451 appears multiple times in the BioShock series.
Bioshock 1 – Inside Twilight Fields Funeral Home (Medical Pavilion)
BioShock 2 – The sauna room in Plasmid Therapies (Adonis Luxury Resort)
Infinite – Near the elevator that takes you to Downtown Emporia
“0451” is a reference that has been used in several games made by previous employees of Looking Glass Studios since the creation of the System Shock game series, considered as the spiritual predecessor of BioShock.
The number was originally thought to be a direct reference to Ray Bradbury’s dystopian novel Fahrenheit 451, in which it represents “the temperature at which book-paper catches fire and burns” but it was latter revealed in multiple interviews with Warren Spector (creator of Deus Ex, System Shock and other games) that 0451 was really the door code to access the Looking Glass Studios offices.
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