Investigate the voice: A child will be calling from a refrigerator near a ruined house south of University Point, east of Jamaica Plain. Upon shooting the handle off the refrigerator a child ghoul by the name of Billy will step out.
Talk to Billy: He will inform the Sole Survivor that he had fled to the fridge when the Great War started and that he had been trapped in the fridge for two hundred years. He tells them that he wants to find his family and return to his home in Quincy.
Escort Billy to his house or sell him: One can either choose to help him get there or sell him to a member of the Gunners named Bullet for caps. Billy's house is not far, but the fastest way there requires swimming to the peninsula with the Atom Cats garage and skirting the outskirts of Quincy, which can attract the attention of enemies in a random encounter spot nearby and the Gunners on the overpass at Quincy.
After talking to Billy one will encounter a Gunner named Bullet on the road to Quincy that wants to buy him. If the Sole Survivor passes the charisma checks, Billy can be sold for a total of 350 caps. To get the charisma checks one may need to ask Bullet how much Billy would be worth. Receiving the caps from Bullet will end the quest. If one kills Bullet afterwards they can talk to Billy again and then take him to his house for an extra 500 caps from the father, which also bypasses the fight in front of the house.
Ending: If one chooses to help Billy get to the house they will find his parents survived the war and are happy to see him. Bullet and some other Gunners will arrive shortly thereafter and demand Billy and his parents step outside.
If one chooses to fight Bullet, Billy's father will give them 250 caps for saving them.
If they chose to lie to Bullet and say the house is empty (very hard speech check), Bullet and his gang will leave the Sole Survivor and the Peabodys alone. Billy's father will award 250 caps for saving them.
Danse will dislike the Sole Survivor telling Billy that his parents are dead (easy persuasion check), but will respond with the line "We're sorry for your loss, son." Hancock however, will like it when the Sole Survivor is honest about this.
Cait will dislike agreeing to find Billy's home. She also hates it if Billy is sold to Bullet. Like Cait, Strong also dislikes the Sole Survivor helping Billy.
There may be a Brotherhood member in the house Billy's parents are in. If the Sole Survivor is allied with the Brotherhood of Steel, he will assist in fighting the Gunners.
If Bullet is killed after declining to sell Billy, the Gunners will not appear at the Peabody house, but the parents will still pay.
If Bullet is killed after passing his Charisma checks, Billy can still be taken to his house for extra (500 total) caps.
Bullet and the Gunners can be convinced that Billy and his parents had fled the building and they will search elsewhere provided the Sole Survivor has enough Charisma. The parents will still award the caps.
Tessa and the high-level Gunners from Quincy Ruins may join Bullet and his lower level henchmen when they attack the house if the Sole Survivor is defending the Peabodys, which makes the fight extremely difficult (if not near impossible) for low level characters. Clearing out Quincy Ruins before taking Billy back to his house seems to solve this problem.
Directly across the road from the fridge where Billy is found there is a small pond containing a leveled suit of power armor.
Although Billy insists that the Sole Survivor must shoot the fridge door to release him, bashing or punching the door will break it, thus saving ammunition.
Oddly enough, the Peabodys cannot be killed by Bullet and his men, even though the player character can fail the quest by killing the parents directly.
Some time after killing Bullet there will be a random encounter where the Sole Survivor will be confronted by someone who says, "Remember Bullet? He was my friend." They will then turn hostile and attack. This person may or may not have backup and may be a raider.
X6-88 dislikes it if the Sole Survivor chooses to defend the Peabodys when confronted by Bullet.
Siding with the Peabodys in this quest is an easy way to get tons of good reputation from "good" companions.
This quest can be triggered by stray bullets hitting the fridge and accidentally releasing Billy.
The following is based on unverified behind the scenes information and has not been confirmed by canon sources.
This quest is a reference to a scene from Indiana Jones and The Kingdom of the Crystal Skull, where Indiana Jones survives a nuclear blast by hiding in a refrigerator. This is the second time in which this is referenced. In Fallout: New Vegas, an explorer hat and skeleton can be found in a fridge if you have the Wild Wasteland trait.
Billy being stuck in the fridge may be a reference to real life deaths caused by children being locked in refrigerators prior to an act passed by Congress in the 1950s. However, Billy says he hid in the refrigerator to escape the bombs. This is a direct reference to the 1963 cold-war commentary film "Ladybug, Ladybug". The cold-war commentary film opens at a rural elementary school facing a warning alert for impending nuclear attack. Near the end of the film, one child, separated from the others, gets inside an old abandoned refrigerator to hide from the bombs.
End of information based on unverified behind the scenes information.
xboxonepcps4 Asking Bullet "What's he worth" will freeze the conversation after Bullet stops talking, resulting in the Sole Survivor either staring at him endlessly or having to walk away.[verified]
ps4 When prompted to "Talk to Bullet" dialogue may not appear. This can be fixed by reloading or killing him.[verified]
pcps4 Bullet may not correctly appear at the Peabodys' house to confront the player. Instead, he will spawn at the center of Quincy, which makes talking to him difficult since Quincy is protected by a large amount of Gunners. PC users may summon him with the console using the command 00028db8.moveto player. Otherwise, fast traveling away and back may resolve the issue. Another simple workaround is to kill Bullet on the first encounter.[verified]
pc If this quest is started before the player has encountered Tessa or Clint in Quincy, they will not drop their respective unique items, making them impossible to acquire.[verified]
pc After the quest is completed, there is a chance that some Gunners will spawn inside the Peabody residence. They will not interact with the Peabodys, and if the Sole Survivor kills them it will not be acknowledged.[verification overdue]