People are so eager to explore the unknown of outer space before realizing how dangerous it can be.The Callisto Protocolis a blood-curdling experience set in 2320 when humans developed interplanetary travel and began establishing colonies throughout the galaxy.

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After crash landing on Callisto, Jacob Lee finds himself falsely imprisoned in Black Iron Prison. Inmates have transformed into terrifying monsters and devouring anything in sight. But the mystery reveals another layer when Jacob discovers a forgotten settlement underneath the prison. We take a look at the brief history of the original colony on Callisto and what happened to its inhabitants.

The following post contains spoilers for The Callisto Protocol. Please do not continue reading unless you have finished the game.

doctor mahler explaining the biophage alien to jacob lee

Arcas Infection

Hidden underneath Black Iron Prison is Callisto’s original colony,Arcas. The few groups of settlers in Arcas were mainlyminersand burrowed deep within Callisto tofind new minerals and valuables. About one year before the events of The Callisto Protocol, theUnited Jupiter Companyarrived on Callisto. The group consisted ofseveral scientists who compiled massive amounts of moneyto fund their research in biology.

The scientists discovered an enormousdead alien creatureburied in the walls. The miners accidentally unearthed the creature while they were digging, and thelarvae infected the Arcas colonistsand caused an outbreak.

jacob lee finding subject zero beneath black iron prison

The Biophage alien came from another planet calledParamoand crash-landed on Callisto. The colonists started mutating into deformed creatures, killing each other, and spreading the virus. When the UJC discovered the remains of Arcas, they believed thealien larvae could accelerate human evolution.

Covering Up The Past

The UJC consists of several scientists and they believed what happened in Arcas could ultimately help the human race. The scientists promised the people of Arcas a brighter future, but all they really wanted was toharvest the larvae.

They beganexperimenting on humansand managed to recreate the mutations, but every test subject except one turned into a brainless monster. The lone person who retained his intelligence was labeledSubject Zero.

Unfortunately, the experiments got out of hand for the UJC, and the infected broke containment. The UJC chose to completely sterilize Arcas andexterminate all of the infected colonists, including Subject Zero.

Not only did the UJC kill all of the colonists, but they also proceeded tobuild Black Iron Prison on top of Arcas. Although the experiments ended with the utter destruction of Arcas, the UJC continued studying the larvae and tried to create another Subject Zero.