Series creator Ken Levine has said the writing for BioShock: Infinite vastly outweighs that of the original BioShock.
"Just one level of BioShock: Infinite writing and the amount of character interaction we have is probably three or four times as much writing as in all of BioShock 1," Levine told Eurogamer.
The Irrational games boss said he didn't know what he was getting into at first.
"When I first came up with these characters Booker and Elizabeth talking to each other and interacting with their world, I didn't consider how much writing that was going to be. I'm doing the vast bulk of it and it can get overwhelming," he said.
"But on the other hand it's a world that I absolutely love to write. Mostly because it's a new challenge. Thinking how these scenes are going to play out, how we keep them interactive and how you communicate the ideas."
BioShock: Infinite is due on PC, PlayStation 3 and Xbox 360 on October 19.