"No matter how hard I try, I'm plagued by the "old world blues". I can change my name, I can shed my past, I can put it all behind me, but it doesn't matter... I'm still the same "Sunshine Jack" I was so many years ago, wasting away those lazy summer days at the co-op." - Janus's Manifesto
Janus, formerly known as Sunshine Jack, is a crazed survivor who is the owner of Sunshine Tidings Co-op. Before the war, he was dedicated to freeing machines from their masters, as seen with Professor Goodfeels, a Mr. Handy he stole and reprogrammed to "just be". Being driven partly insane due to radiation, exposure, and mild cannibalism, Janus has become even more obsessed with freeing the machines from their enslavement. Consumed by his crazed fixation of freeing the enslaved machines, his new object of fascination is the player, who he believes to be HR-D4.
"Johnny and Allen'd pick up old Mister Handys and Protectrons for us to reprogram. We'd set 'em free. Wipe their memories and give them a new life, free from their overlords.
That's what I wanted for the Snake. I wanted to give the new start I couldn't give myself."
Janus has killed several people who he believed were tracking down HR-D4. On the bodies of his recent victims, the player can usually find Janus' calling cards: the smiley hood and ominous notes left for the player, who he refers to as "the Snake".
During the player's expedition into Parsons State Insane Asylum, the player eventually succumbes to their insanity partly due to their exposure to Lorenzo Cabot's psychological influence. The player fades into a blackout characterized by total amnesia and vivid hallucinations, known as a fugue state. During this, Janus apparently encounters and "rescues" the player, taking them to Mount a Desert Island in an effort to prevent the Enclave from tracking them down.
When the player finally confront Janus, he is apparently injured from a fight with Hunters who attempted to board the ship. The player is then given the choice of either sparing him or killing him. If the player kills him, they find Janus's Manifesto on his corpse, thought this can be pick pocketed from him instead. If he isn't killed on the Island, it is believed that he lives on to become the founder of the Railroad, a group dedicated to freeing oppressed synths from their captors.