2K has revealed that Digital Extremes is developing the multiplayer component of BioShock 2, and it's set before the fall of Rapture.

Promising a "rich prequel experience", it's an experience-driven battle between plasmid test subjects working for Sinclair Solutions.

Players will learn more about the fall of Rapture and get to see it before the fall, with areas in and around Kashmir Restaurant and Mercury Suites (presumably among others) reworked for FPS multiplayer.

There's not much detail on the experience system yet, but 2K says has said it will feed into weapon, plasmid and tonic unlocks, and that you'll ultimately be able to kit out your player with any of hundreds of combinations.

"The fans asked for a multiplayer experience and we answered," said Christoph Hartmann, president of 2K.

"With Digital Extremes delivering a multiplayer experience for BioShock 2 that features all of the things that make BioShock unique, we’re holding ourselves to a high standard so that we can deliver the depth and variety that fans of the BioShock universe demand."