Warning: BioShock Infinite spoilers ahead!
So, the end of BioShock Infinite is confusing. It does a reveal, then another, then another, and it feels like half of the ending sequence is spent explaining the other half. And the explations that aren’t right at the end are packed into the easy-to-miss audiologs scattered around the world. For those of you who are still baffled, here is my explanation:
What? You haven’t completed BioShock Infinite yet? Go away! Why did you click this link? This game puts a lot of its emotional payload inside of big reveals, so spoilers really matter. Anyway. Final warning.
So the good guy is also the bad guy? And the woman you saved is also the child you lost? And the scientist who created the problem also devised the solution? And the only way to stop the bad guy is to kill yourself? What does it all mean, and what is the game trying to say? The best way to unravel this is by going over the plot in chronological order instead of the order it’s revealed to us in the game.
The events begin with the massacre at Wounded Knee. Booker DeWitt – accused by his compatriots of having “teepees in his family tree” – wanted to prove himself as loyal, so he became even more savage than his fellow soldiers. He burned women and children alive in their tents and killed as many people as he could. After the war, these deeds haunted him. He sought comfort in religion. And here we have our big split.
The most important thing to note here is that the world of BioShock Infinite uses the many-worlds interpretation where everything that can happen, does happen, along one of the endless branches of an ever-splitting set of possible realities. (This is a real theory, and it was popularized by theoretical physicist Bryce DeWitt.)
In one universe, Booker backs out of baptism at the last second. He figures he doesn’t deserve to be forgiven, and the crimes he’s perpetrated can’t be washed away with water. He walks away from religion and instead distracts himself from his past with booze and gambling. He ends up with a woman, gets her pregnant, and she dies in childbirth. This leaves Booker alone, with heaps of gambling debts, and little baby Anna to raise by himself.
In the other universe, Booker accepts his baptism. When he emerges from the water he renames himself Comstock. The process seems to give him new purpose in life. He becomes a preacher and builds a congregation. He seems to have a twisted view of both baptism and his religion. Instead of repenting of his evil, he acts like baptism is some kind of “get out of guilt for free card.” Instead of feeling remorse at his crimes, he celebrates them and uses them to build his persona as a heroic figure.
He teams up with Dr. Lutece. He provides the funding for her science, and she provides the dimensional tears that allow Comstock to peer into the future. With this tool, Comstock is able to make himself into a prophet. His cult grows, his wealth grows, he marries Lady Comstock, and eventually he founds the flying city of Columbia.
At some point Comstock gets the idea to baptize the world in fire. Baptism worked so well for him, so he figures it will be good for the human race in a “doomsday that kills all unbelievers” kind of way. Unfortunately for his scheme, peering through the tears has aged Comstock. He’s not going to live long enough to see it through. He needs an heir. However, his time-peeking has also sterilized him.
With the help of Lutece, he jumps to one of these side-universes to buy baby Anna from the alcoholic loser Booker. This arrangement would naturally appeal to both men. Comstock would like the idea because the little girl would still be “his” in a genetic sense. Booker would like the idea because he’d be solving his gambling debts and giving his little girl a proper home with a family that wants her.
Booker backs out of the agreement at the last minute. He tries to rescue his kid from the hands of Comstock just as Comstock is slipping back into his own universe. They struggle over the kid and the tear slams shut on baby Anna’s finger, leaving a tiny part of her in Booker’s universe while the rest of her is living in Comstock’s.
Comstock renames the child Elizabeth and sticks her in a tower. Having her body split between universes has given her the ability to open not just tears back to her own universe, but to any universe she likes. Dr. Lutece comes up with the siphon, which will deaden Elizabeth’s powers and prevent her from escaping.
The sudden appearance of a new baby upsets Lady Comstock. She figures her husband is just cheating on her and threatens to tell everyone. Comstock has her killed.
Not much happens while the girl is growing up. About the only notable thing is that Dr. Lutece opens a tear and pulls through a different version of herself from another universe. This Dr. Lutece is a man. She calls him her “brother” and things are kind of weird for a bit but everyone gets used to the idea.
Comstock begins to see Lutece as a loose end and hires his industrialist buddy Fink to have them both killed in a way that looks like an accident. Fink arranges for an equipment malfunction in the Lutece lab. Since the sabotaged machine was one of the dimensional-hopping gizmos, it doesn’t actually kill the Lutece “twins” outright. Instead it maroons them in some sort of confusing state of potential death, or scattered across several realities, or whatever. The point is, the Lutece twins are now magical people that hop in and out of the story as needed and say cryptic things.
The twins figure out what Comstock is up to and decide to stop him. So, they pop over to the other universe and get Booker. Being dragged into the same universe as his other self scrambles his memories and gives the writers a handy excuse to have him know or not know anything they like. The twins send him after Elizabeth, figuring that Comstock’s plans will fail without the girl.
Congratulations, it is now 1912 and we are at the very start of the game.
There are a lot of hints that this plan doesn’t work on the first try. Either the twins loop through time or they just jump to other universes to grab more versions of Booker to throw at the problem. Note that when you die in the game and Elizabeth isn’t around, you wake up on the floor of the Lutece office. You go through the door to find yourself right back at the battlefield where you fell. (This being BioShock Infinite‘s version of the Vita Chamber respawn mechanic.) It’s entirely possible that every time you die, the twins grab a different Booker and dump him into the Comstock universe. Since you tend to mix memories with other versions of yourself when you change universes, this would let the fresh Booker pick up where the previous Booker left off.
Regardless of how it works, Booker is set loose in the Comstock universe. He kills dudes, rescues Elizabeth, kills more dudes, loses Elizabeth, catches her again, they make friends, they change universes a couple of times, a rebellion happens, they fight the ghost of Lady Comstock, and they look through some dimensional tears that explain the plot to them and to the audience. During all of this, there are countless references to baptism and to Wounded Knee.
(Note that the game takes place in 1912 and Wounded Knee happened in 1890. Since the age given for Booker during the game is 38, that means that Booker was 16 at Wounded Knee. That’s pretty young to be in the military, but not unheard of in those days.)
Elizabeth gets recaptured again and we have a little detour where we see the future-world destroyed by fire.
She saves Booker so Booker can save her, and the two of them resume their quest. Booker finally catches up with Comstock and drowns his alter-ego in a baptismal pool. He doesn’t recognize himself because Comstock is aged and has a massive beard. (And a different voice actor. I call shenanigans.)
Once the siphon is destroyed, Elizabeth can move freely between dimensions and see all the possibilities. This leads to the ending that everyone finds so baffling, where the two of you universe-hop and the game tries to fill in a bunch of the stuff I outlined above. The game is explaining the ending as it’s happening, which kind of takes the punch out of it.
The idea is that there isn’t just a Comstock universe and a Booker universe. Sure, we started with that, but the universes continued to split as time went on. A universe where Comstock married one woman, or another, or made peace with Fink, or became his enemy, and so on. The possibility space branched off, over and over, so that there are now “a million million” universes with Comstock. (The Booker universe branches as well, but since all he does is drink they probably all look basically the same.)
Assuming you don’t want to visit a million million worlds and personally murder Comstock in each, the only way to really stop Comstock’s plans is to go back to the original split: Go back to the original baptism.
This is the part of the game where people usually have trouble. Instead of going to the past and seeing young Booker in the process of baptism, you become teenage Booker, but with all of your memories intact. Then Elizabeth drowns you – or you choose it, whatever – and all of the Comstock possibilities collapse. Instead of a universe split that leads to Booker or Comstock, we now have a universe split that leads to Booker or Dead Booker.
This brings us a slight paradox: If no Comstock, then Comstock never bought Anna from Booker. This means no Elizabeth and no universe-hoping to kill Comstock. This leads to the post-credits stinger where – we assume – Booker and Anna are still together and Booker has a chance to clean up and live a normal life with her.
This explanation isn’t perfect or complete, and it doesn’t begin to touch on the emotional, spiritual, social, or political themes the game deals with. I know I’m still missing about 8 of the game’s 80 audiologs, so there are still details to be filled in. But hopefully what we have here can help you understand the ending well enough that you can ponder the spiritual and political stuff yourself.