What happened at the end?
Do a Google search for “BioShock Infinite ending,” and you’ll find pages upon pages of interpretations, theories, and all-out crazy guesses. We even have an incredibly popular post here on GamesBeat from community writer Michael Kyle in which he offers his own meticulously organized thoughts on what exactly happens. Here’s the short version of the ending: Booker discovers that he and Comstock are the same person from different universes, and then this happens.
So Booker drowns at the end. But how does that fix anything?
Another refresher: BioShock Infinite subscribes to the “many-worlds interpretation” of quantum mechanics. Oversimply put, every decision anyone makes anywhere creates a new universe, and as many universes as outcomes exist. So in some realities, Airplane! is a way shorter movie because one or more members of the flight crew picked the chicken over the fish.
Internet discussions, like this one at IGN, are full of people presenting their cases, but two general interpretations stand out.
The hopeful ending
This theory, which is the one that Mr. Kyle’s article endorses, says that the various Elizabeths and Annas drown Booker after he decides to accept the baptism but before he actually goes through with it. So Booker never becomes Comstock, which means that Columbia never exists and the events of the game never happen. Meanwhile, the branch containing the relatively good Booker continues on.
The post-credits scene — in which Booker goes to Anna’s nursery to see if she’s there — supports this reading because with no Comstock, DeWitt and his daughter aren’t separated. This analysis points out that the calendar on Booker’s desk shows the date that he originally turned Anna over to Robert Lutece. In this interpretation, then, the universe — now free of Comstock’s meddling — has reset to the moment at which the cross-dimensional damage occurred.
This theory does have a possible issue, though: the many-worlds interpretation may not work that way. This leads to:
The bleak ending
In this reading, every decision Booker has made his entire life has split the universe, culminating (for our purposes) in a single instance where Booker was or was not baptized after the atrocities he committed at Wounded Knee. Other Booker DeWitts exist, but some might have decided to make handcrafted furniture instead of joining the Army. Maybe some died when they were children. Some might have even been women with totally different lives. Rosalind and Robert Lutece are differently gendered versions of the same person, so maybe some Betty DeWitts also exist somewhere.
From this cloud of Bookers (and, perhaps, Bettys), one emerges: the Booker who has made all the choices that lead to this particular moment. This theory says that resolving the DeWitt/Comstock conflict hinges upon only one Booker ever being in a position to decide whether to accept the baptism. Here’s why:
From that decision, infinite new worlds emerge. Maybe a world exists in which Booker doesn’t take up gambling. Maybe in another one, Comstock wears a funny hat, and nobody knows why. But because the existences of the Booker-with-money-verse and the funny-hat-verse depend entirely on DeWitt’s original choice in that river, they will both cease to exist if he never makes that choice.
The only way to keep Comstock from building Columbia as a flying fortress of fiery death-hate is to keep him from ever existing in the first place. The only way to do that is to kill Booker — the one Booker who reaches that point in the river — before he decides either way. The bleak-enders say that it’s just not possible to trim offending twigs from the multiverse; you have to cut off the entire branch.
But what about that post-credits scene?
That little bonus bit, which features a decidedly undrowned Booker, is the bleak ending’s biggest hurdle. Because Anna/Elizabeth was born after the baptism, how can she exist here?
One possibility, described in that same IGN discussion mentioned above, is that Booker’s death creates a grandfather paradox (if you go back in time and kill your grandfather before he marries your grandmother, you’ll prevent your own birth, which means that you can’t travel back in time to kill your grandfather). Because a paradox is the sort of thing that could destroy the entire space-time continuum — according to Back to the Future‘s Emmett Brown, anyway — nature prefers to sort them out. In this case, the theory says:
[T]he choice to accept the baptism creates a paradox, meaning it is not a possibility. This means that the only possibility allowed by nature is to refuse the baptism, making the refusal no longer a variable but a constant. Thanks to Elizabeth, no branching universes are created at this point, and Booker goes on to raise Anna without her being taken away by an alternate version of himself.
A slightly less complicated version is that the final scene depicts a Booker who decided not to even go to the river for the baptism but whose life otherwise perfectly mirrors that of the Booker we had controlled during the game. But I’m not sure how satisfying that theory is.
Now that we all have headaches, let’s try something easier.