Hold on to your hats: Ken Levine's Irrational Games has just announced BioShock: Infinite - see the first screenshots below.
The spin-off's set in the flying city of Colombia - a sort of Rapture in the clouds.
Infinite looks set to reintroduce plasmids, a brash art style and a version of the Big Daddy. We even thought we spied Andrew Ryan in one frame.
The bad news? It's out in 2012 - that's five years in development. Booo...
For the first details and impressions read our BioShock: Infinite gameplay preview.