I'm going to start by stating the obvious: you should only read this if you've already finished BioShock Infinite, or if you don't mind having the plot hung in front of you in its birthday suit. If you want to experience it first, then bookmark this shizzle and come back when you have.
You're back? Good.
Another thing: if you haven't finished it, then why aren't you playing it right now? Go on, play it. Would you kindly go play it? Do you even row, bro? Do you?
Anyway, as the title helpfully suggests, there may be massive spoilers after this line break.